diff --git a/CSU/1120.cpp b/CSU/1120.cpp
new file mode 100644
index 0000000..238022c
--- /dev/null
+++ b/CSU/1120.cpp
@@ -0,0 +1,58 @@
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+
+#include <vector>
+#include <algorithm>
+using namespace std;
+
+namespace LCIS_INT_LESSMEM
+{
+    const int MAXL=1024;
+    int ldp[MAXL];
+    int deal(int* pa,int na,int *pb,int nb)
+    {
+        memset(ldp,0,MAXL*sizeof(int));
+        for(int i=1;i<=na;i++)
+        {
+            int k=0;
+            for(int j=1;j<=nb;j++)
+            {
+                if(pa[i]>pb[j]) k=max(k,ldp[j]);
+                else if(pa[i]==pb[j])
+                {
+                    ldp[j]=k+1;
+                }
+            }
+        }
+        int ans = 0;
+        for(int i = 1; i <= nb; i++) ans = max(ans, ldp[i]);
+        return ans;
+    }
+}
+
+/// CSUOJ 1120
+int a[1024];
+int b[1024];
+int main()
+{
+    int t;
+    scanf("%d",&t);
+    while(t--)
+    {
+        int na;
+        scanf("%d",&na);
+        for(int i=1;i<=na;i++)
+        {
+            scanf("%d",&a[i]);
+        }
+        int nb;
+        scanf("%d",&nb);
+        for(int i=1;i<=nb;i++)
+        {
+            scanf("%d",&b[i]);
+        }
+        printf("%d\n",LCIS_INT_LESSMEM::deal(a,na,b,nb));
+    }
+    return 0;
+}
diff --git a/HDOJ/2854.cpp b/HDOJ/2854.cpp
new file mode 100644
index 0000000..2b914e1
--- /dev/null
+++ b/HDOJ/2854.cpp
@@ -0,0 +1,66 @@
+#include <cstdio>
+#include <cstring>
+#include <cstdlib>
+
+using namespace std;
+
+/*
+int main()
+{
+    /// Test Program
+    int N;
+    for(N=1;N<5005;N++)
+    {
+        bool isOK=false;
+        for(int A=1;A<=N;A++)
+        {
+            for(int B=1;B<=N;B++)
+            {
+                if((A*A*B+1)%N==0)
+                {
+                    if((A*A+B)%N==0)
+                    {
+                        //printf("A=%d B=%d\n",A,B);
+                        isOK=true;
+                    }
+                    else
+                    {
+                        goto OUT;
+                    }
+                }
+            }
+        }
+        if(isOK)
+        {
+            printf("%d,",N);
+        }
+        OUT:continue;
+    }
+}
+//*/
+int a[]={1,2,3,4,5,6,8,10,12,15,16,20,24,30,40,48,60,80,120,240};
+const int sza=sizeof(a)/sizeof(int);
+
+int main()
+{
+    int t;
+    scanf("%d",&t);
+    while(t--)
+    {
+        int x;
+        scanf("%d",&x);
+        bool isFound=false;
+        for(int i=0;i<sza;i++)
+        {
+            if(a[i]==x)
+            {
+                printf("YES\n");isFound=true;break;
+            }
+        }
+        if(!isFound)
+        {
+            printf("NO\n");
+        }
+    }
+    return 0;
+}
diff --git a/HDOJ/5706.cpp b/HDOJ/5706.cpp
new file mode 100644
index 0000000..11a46ed
--- /dev/null
+++ b/HDOJ/5706.cpp
@@ -0,0 +1,63 @@
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+using namespace std;
+
+char mp[1024][1024];
+
+int cat=0;
+int girl=0;
+
+void dp_girl(int i,int j,int step)
+{
+    switch(step)
+    {
+        case 1:if(mp[i][j]!='i') return;break;
+        case 2:if(mp[i][j]!='r') return;break;
+        case 3:if(mp[i][j]!='l') return;else ++girl;return;break;
+    }
+    dp_girl(i+1,j,step+1);
+    dp_girl(i,j+1,step+1);
+    dp_girl(i-1,j,step+1);
+    dp_girl(i,j-1,step+1);
+}
+
+void dp_cat(int i,int j,int step)
+{
+    switch(step)
+    {
+        case 1:if(mp[i][j]!='a') return;break;
+        case 2:if(mp[i][j]!='t') return;else ++cat;return;
+    }
+    dp_cat(i+1,j,step+1);
+    dp_cat(i,j+1,step+1);
+    dp_cat(i-1,j,step+1);
+    dp_cat(i,j-1,step+1);
+}////
+int main()
+{
+    int t;
+    scanf("%d",&t);
+    while(t--)
+    {
+        int n,m;
+        scanf("%d %d",&n,&m);
+        cat=0;
+        girl=0;
+        memset(mp,0,1024*1024);
+        for(int i=1;i<=n;i++)
+        {
+            scanf("%s",&mp[i][1]);
+        }
+        for(int i=1;i<=n;i++)
+        {
+            for(int j=1;j<=m;j++)
+            {
+                if(mp[i][j]=='g') dp_girl(i,j,0);
+                else if(mp[i][j]=='c') dp_cat(i,j,0);
+            }
+        }
+        printf("%d %d\n",girl,cat);
+    }
+    return 0;
+}
diff --git a/NYOJ/38.cpp b/NYOJ/38.cpp
new file mode 100644
index 0000000..4a02f3b
--- /dev/null
+++ b/NYOJ/38.cpp
@@ -0,0 +1,91 @@
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <vector>
+#include <algorithm>
+using namespace std;
+
+#define MAXPOINT 512
+
+//#define dprintf(A,B...) printf(A,##B)
+#define dprintf(A,B...)
+
+int groupid[MAXPOINT];
+
+struct EDGE
+{
+    int u,v;
+    int w;
+};
+
+bool cmp_d(const EDGE& a,const EDGE& b)
+{
+    if(a.w==b.w)
+    {
+        if(a.u==b.u)
+        {
+            return a.v<b.v;
+        }
+        return a.u<b.u;
+    }
+    return a.w<b.w;
+}
+int findgroup(int pos)
+{
+    int f=groupid[pos];
+    while(groupid[f]!=f) f=groupid[f];
+    return f;
+}
+int main()
+{
+    int n;
+    scanf("%d",&n);
+    while(n--)
+    {
+        int V,E;
+        scanf("%d %d",&V,&E);
+        vector<EDGE> vec;
+        EDGE tmp;
+        for(int i=0;i<E;i++)
+        {
+            scanf("%d %d %d",&tmp.u,&tmp.v,&tmp.w);
+            if(tmp.u>tmp.v)
+                swap(tmp.u,tmp.v);
+            vec.push_back(tmp);
+        }
+        sort(vec.begin(),vec.end(),cmp_d);
+        for(int i=0;i<MAXPOINT;i++)
+        {
+            groupid[i]=i;
+        }
+        int totalw=0;
+        int choosed=0;
+        for(int i=0;i<E&&choosed<V-1;i++)
+        {
+            int KA=findgroup(vec.at(i).u);
+            int KB=findgroup(vec.at(i).v);
+            if(KA!=KB)
+            {
+                /// Choose this Edge.
+                dprintf("Choose %d %d %d\n",vec.at(i).u,vec.at(i).v,vec.at(i).w);
+                choosed++;
+                totalw+=vec.at(i).w;
+                groupid[vec.at(i).u]=KA;
+                groupid[vec.at(i).v]=KA;
+                groupid[KB]=KA;
+                dprintf("%d <- %d\n",vec.at(i).u,vec.at(i).v);
+            }
+        }
+        vector<int> dpos;
+        int dtmp;
+        for(int i=0;i<V;i++)
+        {
+            scanf("%d",&dtmp);
+            dpos.push_back(dtmp);
+        }
+        sort(dpos.begin(),dpos.end());
+        totalw+=dpos.at(0);
+        printf("%d\n",totalw);
+    }
+    return 0;
+}
diff --git a/NYOJ/38_17age.cpp b/NYOJ/38_17age.cpp
new file mode 100644
index 0000000..3387fe5
--- /dev/null
+++ b/NYOJ/38_17age.cpp
@@ -0,0 +1,72 @@
+#include<iostream>
+#include<algorithm>
+#include<stdio.h>
+#include<string.h>
+#include<math.h>
+using namespace std;
+const int maxn=505;
+const int INF=0x3f3f3f3f;
+int map[maxn][maxn];
+int dis[maxn];
+int vis[maxn];
+int N;//N组测试数据
+int V;//点的数量
+int E;//边的数量
+int min_num;//最小外接花费
+void init()
+{
+    scanf("%d%d",&V,&E);
+    for(int i=0; i<=V; i++)//初始化图
+        for(int j=0; j<=V; j++)
+            i==j?map[i][j]=0:map[i][j]=INF;
+    while(E--)//建图
+    {
+        int a,b,c;
+        scanf("%d%d%d",&a,&b,&c);
+        map[a][b]=c;//无向图
+        map[b][a]=c;
+    }
+    min_num=INF;
+    for(int i=1; i<=V; i++)
+    {
+        int x;
+        scanf("%d",&x);
+        min_num=min(min_num,x);//生成树连接到外界的最小花费
+        dis[i]=map[i][1];//从1开始构造最小生成树
+    }
+    memset(vis,0,sizeof(vis));
+    vis[1]=1;//0代表是外界
+}
+void Prim()
+{
+    int min_cost=0;//初始化最小花费
+    for(int i=1; i<V; i++)
+    {
+        int minn=INF;
+        int point_minn;
+        for(int j=1; j<=V; j++)
+            if(vis[j]==0&&minn>dis[j])
+            {
+                point_minn=j;
+                minn=dis[j];
+            }
+        if(minn==INF)
+            break;
+        min_cost+=dis[point_minn];
+        vis[point_minn]=1;
+        for(int j=1; j<=V; j++)
+            if(vis[j]==0&&dis[j]>map[point_minn][j])
+                dis[j]=map[point_minn][j];
+    }
+    printf("%d\n",min_cost+min_num);
+}
+int main()
+{
+    scanf("%d",&N);
+    while(N--)
+    {
+        init();
+        Prim();
+    }
+    return 0;
+}
diff --git a/NYOJ/38_张云聪.cpp b/NYOJ/38_张云聪.cpp
new file mode 100644
index 0000000..bf046fc
--- /dev/null
+++ b/NYOJ/38_张云聪.cpp
@@ -0,0 +1,71 @@
+ 
+#include<queue>
+#include<iostream>
+#include<cstring>
+#include<cstdio>
+#include<numeric>
+#include<algorithm>
+using namespace std;
+#define CLR(arr,val) memset(arr,val,sizeof(arr))
+struct Node
+{
+	Node(){}
+	Node(int num,int len):len(len),num(num){}
+	int len,num;
+};
+bool operator<(const Node& n1,const Node& n2)
+{
+	return n1.len>n2.len;
+}
+const int MAX=510;
+const int MAXE=250000;
+int Head[MAX],Next[MAXE],Num[MAXE],Len[MAXE];
+int Dis[MAX],top;
+void add(int u,int v,int len)
+{
+	Num[top]=v;
+	Next[top]=Head[u];
+	Len[top]=len;
+	Head[u]=top++;
+}
+bool InQ[MAX];
+int main()
+{
+	//freopen("input.txt","r",stdin);
+	priority_queue<Node> q;
+	int t,m,n,a,b,l;
+	scanf("%d",&t);
+	while(t--)
+	{
+		top=0;CLR(Head,-1);
+		CLR(Dis,0x3f);
+		scanf("%d%d",&m,&n);
+		for(int i=0;i!=n;i++)
+		{
+			scanf("%d%d%d",&a,&b,&l);
+			add(a-1,b-1,l);add(b-1,a-1,l);
+		}
+		Dis[0]=0;
+		q.push(Node(0,0));
+		while(!q.empty())
+		{
+			Node t=q.top();q.pop();
+			if(Dis[t.num]!=t.len) continue;
+			for(int i=Head[t.num];i!=-1;i=Next[i])
+			{
+				if(Dis[Num[i]]>Len[i])
+				{
+					Dis[Num[i]]=Len[i];
+					q.push(Node(Num[i],Len[i]));
+				}
+			}
+		}
+		int minl=0x3f3f3f3f;
+		for(int i=0;i!=m;i++)
+		{
+			scanf("%d",&l);
+			minl=min(minl,l);
+		}
+		printf("%d\n",accumulate(Dis,Dis+m,0)+minl);
+	}
+}        
diff --git a/QUSTOJ/1026.cpp b/QUSTOJ/1026.cpp
new file mode 100644
index 0000000..d3083f2
--- /dev/null
+++ b/QUSTOJ/1026.cpp
@@ -0,0 +1,32 @@
+#include <iostream>
+#include<cstdio>
+#include<cmath>
+using namespace std;
+int n;
+double A[110][110];
+int main()
+{
+    scanf("%d",&n);n++;
+    for(int i=1;i<n;i++)
+        for(int j=1;j<=n;j++)
+            scanf("%lf",&A[i][j]);
+    for(int i=1;i<n;i++)
+    {
+        int np=i;
+        for(int j=i+1;j<n;j++)if(abs(A[np][i])<abs(A[j][i]))np=j;
+        if(np!=i)swap(A[np],A[i]);
+        //print();
+        double GD=A[i][i];
+        for(int j=1;j<=n;j++)A[i][j]/=GD;
+        for(int j=1;j<n;j++)
+        if(j!=i){
+            GD=A[j][i];
+            for(int k=1;k<=n;k++)
+            A[j][k]-=GD*A[i][k];
+        }
+    }
+    for(int i=1;i<n-1;i++)
+    printf("%d ",(int)(round)(A[i][n]));
+    printf("%d\n",(int)(round)(A[n-1][n]));
+    return 0;
+}
diff --git a/QUSTOJ/1125.cpp b/QUSTOJ/1125.cpp
new file mode 100644
index 0000000..2a11ca4
--- /dev/null
+++ b/QUSTOJ/1125.cpp
@@ -0,0 +1,49 @@
+#include <cstdio>
+#include <cstdlib>
+#include <vector>
+#include <algorithm>
+using namespace std;
+//Written by Coffee. 判断素数
+bool isPrime(int num)
+{
+	if (num == 2 || num == 3)
+	{
+		return true;
+	}
+	if (num % 6 != 1 && num % 6 != 5)
+	{
+		return false;
+	}
+	for (int i = 5; i*i <= num; i += 6)
+	{
+		if (num % i == 0 || num % (i+2) == 0)
+		{
+			return false;
+		}
+	}
+	return true;
+}
+
+int main()
+{
+    int n,k;
+    vector<int> vec;
+    scanf("%d %d",&n,&k);
+    int tmp;
+    for(int i=0;i<n;i++)
+    {
+        scanf("%d",&tmp);
+        vec.push_back(tmp);
+    }
+    sort(vec.begin(),vec.end());
+    int m=vec.at(n-k)-vec.at(k-1);
+    if(isPrime(m))
+    {
+        printf("YES\n");
+    }
+    else
+    {
+        printf("NO\n");
+    }
+    return printf("%d\n",m),0;
+}
diff --git a/QUSTOJ/1181.cpp b/QUSTOJ/1181.cpp
new file mode 100644
index 0000000..4c17c9f
--- /dev/null
+++ b/QUSTOJ/1181.cpp
@@ -0,0 +1,46 @@
+#include<iostream>
+using namespace std;
+int main()
+{
+    int a,b,mx=0;
+    int i;
+    int m,n,v[61]= {0},p[61]= {0},q;
+    int v1[61]= {0},v2[61]= {0},p1[61]= {0},p2[61]= {0};
+    int f[50001]= {0};
+    cin>>m>>n;
+    m/=10;
+    for(i=1; i<=n; i++)
+    {
+        cin>>a>>b>>q;
+        a/=10;
+        if(q!=0)
+        {
+            if(v1[q]==0)
+            {
+                v1[q]=a;
+                p1[q]=b;
+            }
+            else
+            {
+                v2[q]=a;
+                p2[q]=b;
+            }
+        }
+        else
+        {
+            v[i]=a;
+            p[i]=b;
+        }
+    }
+    for(int i=1; i<=n; i++)
+        for(int j=m; j>=v[i]; j--)
+        {
+            f[j]=max(f[j],f[j-v[i]]+v[i]*p[i]);
+            if(j-v1[i]-v[i]>=0)f[j]=max(f[j],f[j-v1[i]-v[i]]+v1[i]*p1[i]+v[i]*p[i]);
+            if(j-v2[i]-v[i]>=0)f[j]=max(f[j],f[j-v2[i]-v[i]]+v2[i]*p2[i]+v[i]*p[i]);
+            if(j-v1[i]-v2[i]-v[i]>=0)f[j]=max(f[j],f[j-v1[i]-v2[i]-v[i]]+v1[i]*p1[i]+v2[i]*p2[i]+v[i]*p[i]);
+            mx=max(f[j],mx);
+        }
+    cout<<mx*10<<endl;
+    return 0;
+}
diff --git a/QUSTOJ/1311_蜘蛛侠.cpp b/QUSTOJ/1311_蜘蛛侠.cpp
new file mode 100644
index 0000000..2e19aeb
--- /dev/null
+++ b/QUSTOJ/1311_蜘蛛侠.cpp
@@ -0,0 +1,201 @@
+/*
+ *  解法: 很明显是几何 + 最小费用最大流, 关键是如何建图.
+ *        1. 设置一个源点和汇点.
+ *        2. 每个lich和每个wisp分别用一个点来表示.
+ *        3. 如果第i个lich能攻击到第j个wisp, 那么在图中从lich[i]到wisp[j]增加一条边, 容量为1, 费用为0.
+ *        4. 每个wisp连一条边到汇点, 容量为1, 费用为0.
+ *        5. 源点到每个lich连k条边, k为每个lich能攻击到的wisp数量, 每条边的容量为1, 第i条边的费用为i * t (i为0 - k-1, t为lich的cooldown时间)
+ *        运行最小费用最大流, 答案就是从源点到lich满流的边, 且费用最大的那条边的费用值.
+ */
+#include <iostream>
+#include <cstring>
+#include <cstdlib>
+#include <cstdio>
+#include <math.h>
+using namespace std;
+const int maxn = 205;
+const double eps = 1e-8;
+typedef int typef;
+typedef int typec;
+#define inff 0x0fffffff
+#define infc 0x0fffffff
+#define V    500
+#define E    200000
+struct network
+{
+    int nv, ne, pnt[E], nxt[E];
+    int vis[V], que[V], head[V], pv[V], pe[V];
+    typef flow, cap[E]; typec cost, dis[E], d[V];
+    void addedge(int u, int v, typef c, typec w)
+    {
+        pnt[ne] = v; cap[ne] = c;
+        dis[ne] = w; nxt[ne] = head[u]; head[u] = ne++;
+        pnt[ne] = u; cap[ne] = 0;
+        dis[ne] = -w; nxt[ne] = head[v]; head[v] = ne++;
+    }
+    int mincost(int src, int sink)
+    {
+        int i, k, f, r; typef mxf;
+        for(flow = 0, cost = 0; ; )
+        {
+            memset(pv, -1, sizeof(pv));
+            memset(vis, 0, sizeof(vis));
+            for(i = 0; i < nv; ++i) d[i] = infc;
+            d[src] = 0; pv[src] = src; vis[src] = 1;
+            for(f = 0, r = 1, que[0] = src; r != f; )
+            {
+                i = que[f++]; vis[i] = 0;
+                if(V == f) f = 0;
+                for(k = head[i]; k != -1; k = nxt[k])
+                    if(cap[k] && dis[k]+d[i] < d[pnt[k]])
+                    {
+                        d[pnt[k]] = dis[k] + d[i];
+                        if(0 == vis[pnt[k]])
+                        {
+                            vis[pnt[k]] = 1;
+                            que[r++] = pnt[k];
+                            if(V == r) r = 0;
+                        }
+                        pv[pnt[k]] = i; pe[pnt[k]] = k;
+                    }
+            }
+            if(-1 == pv[sink]) break;
+            for(k = sink, mxf = inff; k != src; k = pv[k])
+                if(cap[pe[k]] < mxf) mxf = cap[pe[k]];
+            flow += mxf; cost += d[sink] * mxf;
+            for(k = sink; k != src; k = pv[k])
+            {
+                cap[pe[k]] -= mxf; cap[pe[k]^1] += mxf;
+            }
+        }
+        return cost;
+    }
+    void init(int v)
+    {
+        nv = v; ne = 0;
+        memset(head, -1, 4 * v);
+    }
+} nw;
+struct Lich
+{
+    double x, y, r;
+    int t;
+    void input()
+    {
+        scanf("%lf %lf %lf %d", &x, &y, &r, &t);
+    }
+} lich[maxn];
+struct Wisp
+{
+    double x, y;
+    void input()
+    {
+        scanf("%lf %lf", &x, &y);
+    }
+} wisp[maxn];
+struct Tree
+{
+    double x, y, r;
+    void input()
+    {
+        scanf("%lf %lf %lf", &x, &y, &r);
+    }
+} tree[maxn];
+int T, N, M, K;
+int ecnt[maxn];
+double Dot(double dx1, double dy1, double dx2, double dy2)
+{
+    return dx1 * dx2 + dy1 * dy2;
+}
+double Dis(double x0, double y0, double x1, double y1, double x2, double y2)
+{
+    double a, b, c;
+    if (fabs(x1 - x2) > fabs(y1 - y2))
+    {
+        b = 1.0;
+        a = b * (y2 - y1) / (x1 - x2);
+        c = -(a * x1 + b * y1);
+    }
+    else
+    {
+        a = 1.0;
+        b = a * (x2 - x1) / (y1 - y2);
+        c = -(a * x1 + b * y1);
+    }
+    return fabs(a * x0 + b * y0 + c) / sqrt(a * a + b * b);
+}
+bool NoCross(int a, int b)
+{
+    int i;
+    for (i = 0; i < K; i++)
+    {
+        if (Dot(tree[i].x - lich[a].x, tree[i].y - lich[a].y, wisp[b].x - lich[a].x, wisp[b].y - lich[a].y) > 0.0 &&
+            Dot(tree[i].x - wisp[b].x, tree[i].y - wisp[b].y, lich[a].x - wisp[b].x, lich[a].y - wisp[b].y) > 0.0 &&
+            Dis(tree[i].x, tree[i].y, lich[a].x, lich[a].y, wisp[b].x, wisp[b].y) < tree[i].r + eps)
+            return false;
+    }
+    return true;
+}
+bool InRound(int i, int j)
+{
+    double dx = lich[i].x - wisp[j].x;
+    double dy = lich[i].y - wisp[j].y;
+    return sqrt(dx * dx + dy * dy) < lich[i].r + eps;
+}
+void BuildGraph()
+{
+    int i, j;
+    for (i = 0; i < N; i++)
+    {
+        ecnt[i] = 0;
+        for (j = 0; j < M; j++)
+        {
+            if (InRound(i, j) && NoCross(i, j))
+            {
+                ecnt[i]++;
+                nw.addedge(i, N + j, 1, 0);
+            }
+        }
+    }
+    for (i = 0; i < N; i++)
+    {
+        for (j = 0; j < ecnt[i]; j++)
+            nw.addedge(N + M, i, 1, lich[i].t * j);
+    }
+    for (i = 0; i < M; i++)
+        nw.addedge(N + i, N + M + 1, 1, 0);
+}
+void Solve()
+{
+    nw.mincost(N + M, N + M + 1);
+    if (nw.flow != M)
+    {
+        printf("-1\n");
+        return;
+    }
+    int ans = 0;
+    for (int p = nw.head[N+M]; p != -1; p = nw.nxt[p])
+    {
+        if (nw.cap[p] == 0 && nw.dis[p] > ans)
+            ans = nw.dis[p];
+    }
+    printf("%d\n", ans);
+}
+int main()
+{
+    int i;
+    for (scanf("%d", &T); T; T--)
+    {
+        scanf("%d %d %d", &N, &M, &K);
+        for (i = 0; i < N; i++)
+            lich[i].input();
+        for (i = 0; i < M; i++)
+            wisp[i].input();
+        for (i = 0; i < K; i++)
+            tree[i].input();
+        nw.init(N + M + 2);
+        BuildGraph();
+        Solve();
+    }
+    return 0;
+}
diff --git a/QUSTOJ/1342.cpp b/QUSTOJ/1342.cpp
new file mode 100644
index 0000000..0d49205
--- /dev/null
+++ b/QUSTOJ/1342.cpp
@@ -0,0 +1,15 @@
+#include <cstdio>
+#define STR_A "6 its factors are 1 2 3 "
+#define STR_B "28 its factors are 1 2 4 7 14 "
+#define STR_C "496 its factors are 1 2 4 8 16 31 62 124 248 "
+#define STR_D "8128 its factors are 1 2 4 8 16 32 64 127 254 508 1016 2032 4064 "
+int main()
+{
+    int n;
+    scanf("%d",&n);
+    if(n>=6) puts(STR_A);
+    if(n>=28) puts(STR_B);
+    if(n>=496) puts(STR_C);
+    if(n>=8128) puts(STR_D);
+    return 0;
+}
diff --git a/QUSTOJ/1372.cpp b/QUSTOJ/1372.cpp
new file mode 100644
index 0000000..8165fb0
--- /dev/null
+++ b/QUSTOJ/1372.cpp
@@ -0,0 +1,14 @@
+#include <cstdio>
+int main()
+{
+    int n;
+    scanf("%d",&n);
+    int f=0;
+    int m=3;
+    for(int i=1;i<=n;i++)
+    {
+        f=(f+m)%i;
+    }
+    printf("%d\n",f+1);
+    return 0;
+}
diff --git a/QUSTOJ/1429.java b/QUSTOJ/1429.java
new file mode 100644
index 0000000..def7a2a
--- /dev/null
+++ b/QUSTOJ/1429.java
@@ -0,0 +1,24 @@
+import java.util.Scanner;
+
+public class Main {
+    public static void main(String[] args) {
+        Scanner in = new Scanner(System.in);
+        int radix = in.nextInt();
+        String s = in.next();
+        StringBuffer s2 = new StringBuffer(s).reverse();
+        int cnt = 0;
+        long x = Long.valueOf(s, radix);
+        while(!s2.toString().equals(s) && cnt <= 30){
+            cnt++;
+            x +=  Long.valueOf(s2.toString(), radix);
+            s = Long.toString(x,radix);
+            s2 = new StringBuffer(s).reverse();
+        }
+        if(cnt > 30){
+            System.out.println("Impossible!");
+        } else {
+            System.out.println("STEP=" + cnt);
+        }
+        in.close();
+    }
+}
diff --git a/QUSTOJ/1429.pas b/QUSTOJ/1429.pas
new file mode 100644
index 0000000..8926fc4
--- /dev/null
+++ b/QUSTOJ/1429.pas
@@ -0,0 +1,33 @@
+const
+  step:integer=0;
+  chars:array[0..15] of char=('0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F');
+var
+  digit:array[char] of integer;
+  i,n,g:integer;
+  m,s:string;
+  ok:boolean;
+begin
+  for i:=0 to 9 do digit[char(ord('0')+i)]:=i;
+  for i:=0 to 5 do digit[char(ord('A')+i)]:=i+10;
+ readln(n);
+readln(s);
+  for i:=1 to length(s) do s[i]:=upcase(s[i]);
+  repeat
+    ok:=true;
+    for i:=1 to length(s) div 2 do
+      if s[i]<>s[length(s)+1-i] then ok:=false;
+    if ok then break;
+    inc(step);
+    m:=s; g:=0;
+    for i:=length(m) downto 1 do
+    begin
+      s[i]:=chars[(digit[m[i]]+digit[m[length(m)+1-i]]+g) mod n];
+      g:=(digit[m[i]]+digit[m[length(m)+1-i]]+g) div n;
+    end;
+    if g>0 then s:=chars[g]+s;
+  until step>=30;
+  if ok then
+    writeln('STEP=',step)
+  else
+    writeln('Impossible');
+end.
diff --git a/QUSTOJ/1433.cpp b/QUSTOJ/1433.cpp
new file mode 100644
index 0000000..4c3fc1b
--- /dev/null
+++ b/QUSTOJ/1433.cpp
@@ -0,0 +1,27 @@
+#include<iostream>
+#include<algorithm>
+#include<string.h>
+using namespace std;
+int main()
+{
+  int a[1001],n,m,i;
+  memset(a,0,sizeof(a));
+  cin>>n;
+  int count=0;
+  for(i=1;i<=n;i++)
+  {
+    cin>>m;
+    a[m]++;
+  }
+  for(i=1;i<=1000;i++)
+    if(a[i]!=0)  count++;
+  cout<<count<<endl;
+  for(i=1;i<=1000;i++)
+    if(a[i]!=0)  cout<<i<<' ';
+  return 0;
+}
+
+/**
+100 765
+19485
+*/
diff --git a/QUSTOJ/1765.c b/QUSTOJ/1765.c
new file mode 100644
index 0000000..4ff7ab4
--- /dev/null
+++ b/QUSTOJ/1765.c
@@ -0,0 +1,58 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+typedef struct
+{
+    double L,R;
+}INUM;
+char str[1024];
+char* format(INUM i)
+{
+    sprintf(str,"(%.2f%+.2fi)",i.L,i.R);
+    return str;
+}
+int main()
+{
+    INUM a,b;
+    scanf("%lf %lf %lf %lf",&a.L,&a.R,&b.L,&b.R);
+    INUM ans;
+    ans.L=a.L+b.L;
+    ans.R=a.R+b.R;
+    printf(format(a));
+    printf("+");
+    printf(format(b));
+    printf("=");
+    printf(format(ans));
+    printf("\n");
+
+    ans.L=a.L-b.L;
+    ans.R=a.R-b.R;
+    printf(format(a));
+    printf("-");
+    printf(format(b));
+    printf("=");
+    printf(format(ans));
+    printf("\n");
+
+    ans.L=a.L*b.L-a.R*b.R;
+    ans.R=a.L*b.R+a.R*b.L;
+    printf(format(a));
+    printf("*");
+    printf(format(b));
+    printf("=");
+    printf(format(ans));
+    printf("\n");
+
+    ans.L=a.L*b.L+a.R*b.R;
+    ans.L/=b.L*b.L+b.R*b.R;
+    ans.R=a.R*b.L-a.L*b.R;
+    ans.R/=b.L*b.L+b.R*b.R;
+    printf(format(a));
+    printf("/");
+    printf(format(b));
+    printf("=");
+    printf(format(ans));
+    printf("\n");
+
+    return 0;
+}
diff --git a/QUSTOJ/1766.c b/QUSTOJ/1766.c
new file mode 100644
index 0000000..375b731
--- /dev/null
+++ b/QUSTOJ/1766.c
@@ -0,0 +1,15 @@
+#include <stdio.h>
+#include <stdlib.h>
+char a[256];
+char b[256];
+char c[256];
+
+int main()
+{
+    for(int i=0;i<5;i++)
+    {
+        scanf("%s %s %s",a,b,c);
+        printf("%s %s %s\n",a,b,c);
+    }
+    return 0;
+}
diff --git a/QUSTOJ/1767.c b/QUSTOJ/1767.c
new file mode 100644
index 0000000..502aa5e
--- /dev/null
+++ b/QUSTOJ/1767.c
@@ -0,0 +1,36 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+typedef struct
+{
+    char name[1024];
+    int id;
+    int ENG,MATH;
+} _sinfo;
+_sinfo sinfo[5];
+int cmp(const void* a,const void* b)
+{
+    int cret;
+    if((cret=strcmp(((_sinfo*)a)->name,((_sinfo*)b)->name))==0)
+    {
+        if(((_sinfo*)a)->ENG==((_sinfo*)b)->ENG)
+        {
+            return ((_sinfo*)a)->MATH - ((_sinfo*)b)->MATH;
+        }
+        else return ((_sinfo*)a)->ENG - ((_sinfo*)b)->ENG;
+    }
+    else return cret;
+}
+int main()
+{
+    for(int i=0;i<5;i++)
+    {
+        scanf("%d %s %d %d",&sinfo[i].id,sinfo[i].name,&sinfo[i].ENG,&sinfo[i].MATH);
+    }
+    qsort(sinfo,5,sizeof(_sinfo),cmp);
+    for(int i=0;i<5;i++)
+    {
+        printf("%d %s %d %d\n",sinfo[i].id,sinfo[i].name,sinfo[i].ENG,sinfo[i].MATH);
+    }
+    return 0;
+}
diff --git a/QUSTOJ/1769.cpp b/QUSTOJ/1769.cpp
new file mode 100644
index 0000000..1d53776
--- /dev/null
+++ b/QUSTOJ/1769.cpp
@@ -0,0 +1,86 @@
+#include <iostream>
+using namespace std;
+const int maxnum = 10005;
+const int maxEdge= 50005;
+const int maxint = 107391822;
+
+// 边，
+typedef struct Edge{
+	int u, v;    // 起点，重点
+	int weight;  // 边的权值
+}Edge;
+
+Edge edge[maxEdge];     // 保存边的值
+int  dist[maxnum];     // 结点到源点最小距离
+
+int nodenum, edgenum, source;    // 结点数，边数，源点
+
+// 初始化图
+void init()
+{
+	// 输入结点数，边数，源点
+	cin >> nodenum >> edgenum ;
+	source=1;
+	for(int i=1; i<=nodenum; ++i)
+		dist[i] = maxint;
+	dist[source] = 0;
+	for(int i=1; i<=edgenum; i++)
+	{
+		cin >> edge[i].u >> edge[i].v >> edge[i].weight;
+		if(edge[i].u == source)          //注意这里设置初始情况
+			dist[edge[i].v] = edge[i].weight;
+
+        /*
+        /// Another
+        edge[i+1].u=edge[i].v;
+        edge[i+1].v=edge[i].u;
+        edge[i+1].weight=-edge[i].weight;
+
+        if(edge[i+1].u == source)          //注意这里设置初始情况
+			dist[edge[i+1].v] = edge[i+1].weight;
+        */
+	}
+}
+
+// 松弛计算
+void relax(int u, int v, int weight)
+{
+	if(dist[v] > dist[u] + weight)
+		dist[v] = dist[u] + weight;
+}
+
+bool Bellman_Ford()
+{
+	for(int i=1; i<=nodenum-1; ++i)
+		for(int j=1; j<=edgenum; ++j)
+			relax(edge[j].u, edge[j].v, edge[j].weight);
+	bool flag = 1;
+	// 判断是否有负环路
+	for(int i=1; i<=edgenum; ++i)
+		if(dist[edge[i].v] > dist[edge[i].u] + edge[i].weight)
+		{
+			flag = 0;
+			break;
+		}
+	return flag;
+}
+int main()
+{
+	//freopen("input3.txt", "r", stdin);
+    init();
+	if(Bellman_Ford())
+        //for(int i = 1 ;i <= nodenum; i++)
+			cout << dist[nodenum] << endl;
+    else
+        throw "WTF??";
+	return 0;
+}
+/*
+4 6
+1 2 -5
+2 3 -6
+1 3 -9
+2 4 -7
+3 4 -8
+1 4 6
+*/
diff --git a/QUSTOJ/1771.c b/QUSTOJ/1771.c
new file mode 100644
index 0000000..0c2e43c
--- /dev/null
+++ b/QUSTOJ/1771.c
@@ -0,0 +1,43 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+int main()
+{
+    int t;
+    scanf("%d",&t);
+    while(t--)
+    {
+        int Y,M,D;
+        scanf("%d %d %d",&Y,&M,&D);
+        struct tm k;
+        memset(&k,0,sizeof(k));
+        k.tm_year=Y-1900;
+        k.tm_mon=M-1;
+        k.tm_mday=D;
+        k.tm_hour=0;
+        k.tm_min=0;
+        k.tm_sec=0;
+        struct tm s;
+        memset(&s,0,sizeof(s));
+        s.tm_year=1990-1900;
+        s.tm_mon=1-1;
+        s.tm_mday=1;
+        s.tm_hour=0;
+        s.tm_min=0;
+        s.tm_sec=0;
+        time_t a=mktime(&k);
+        time_t b=mktime(&s);
+        int day=(a-b)/(3600*24);
+        if(day%5<3)
+        {
+            printf("1\n");
+        }
+        else
+        {
+            printf("0\n");
+        }
+    }
+    return 0;
+}
diff --git a/QUSTOJ/1772.c b/QUSTOJ/1772.c
new file mode 100644
index 0000000..9915080
--- /dev/null
+++ b/QUSTOJ/1772.c
@@ -0,0 +1,14 @@
+#include <stdio.h>
+#include <stdlib.h>
+int a[8];
+int cmp(const void* a,const void* b)
+{
+    return *(int*)b-*(int*)a;
+}
+int main()
+{
+    for(int i=0;i<3;i++) scanf("%d",&a[i]);
+    qsort(a,3,sizeof(int),cmp);
+    for(int i=0;i<2;i++) printf("%d ",a[i]);
+    return printf("%d\n",a[2]),0;
+}
diff --git a/QUSTOJ/1773.c b/QUSTOJ/1773.c
new file mode 100644
index 0000000..af51d1b
--- /dev/null
+++ b/QUSTOJ/1773.c
@@ -0,0 +1,15 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+char a[1024];
+int main()
+{
+    gets(a);
+    int L=strlen(a);
+    for(int i=L-1;i>=0;i--)
+    {
+        printf("%c",a[i]);
+    }
+    printf("\n");
+    return 0;
+}
diff --git a/QUSTOJ/1774.c b/QUSTOJ/1774.c
new file mode 100644
index 0000000..62ace26
--- /dev/null
+++ b/QUSTOJ/1774.c
@@ -0,0 +1,15 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+int main()
+{
+    int tmp;
+    int odd=0;
+    int even=0;
+    while(scanf("%d",&tmp)==1)
+    {
+        if(tmp%2==1) odd+=tmp;
+        else even+=tmp;
+    }
+    return printf("%d %d\n",odd,even),0;
+}
diff --git a/QUSTOJ/1775.c b/QUSTOJ/1775.c
new file mode 100644
index 0000000..94bc2fc
--- /dev/null
+++ b/QUSTOJ/1775.c
@@ -0,0 +1,18 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+int main()
+{
+    int n;
+    scanf("%d",&n);
+    double ans=0;
+    if(n%2==1)
+    {
+        for(int k=1;k<=n;k+=2) ans+=1.0/k;
+    }
+    else
+    {
+        for(int k=2;k<=n;k+=2) ans+=1.0/k;
+    }
+    return printf("%f\n",ans),0;
+}
diff --git a/QUSTOJ/1776.c b/QUSTOJ/1776.c
new file mode 100644
index 0000000..dd1a705
--- /dev/null
+++ b/QUSTOJ/1776.c
@@ -0,0 +1,18 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+char str[128];
+int main()
+{
+    int t;
+    scanf("%d",&t);
+    int sc=0;
+    int tmp;
+    while(t--)
+    {
+        scanf("%d",&tmp);
+        if(tmp>sc) scanf("%s",str),sc=tmp;
+        else scanf("%*s");
+    }
+    return printf("%d %s\n",sc,str),0;
+}
diff --git a/QUSTOJ/1777.c b/QUSTOJ/1777.c
new file mode 100644
index 0000000..0603fa8
--- /dev/null
+++ b/QUSTOJ/1777.c
@@ -0,0 +1,18 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+int main()
+{
+    int mi,mj;
+    int mv=0;
+    for(int i=1;i<=3;i++)
+    {
+        for(int j=1;j<=4;j++)
+        {
+            int tmp;
+            scanf("%d",&tmp);
+            if(tmp>mv) mi=i,mj=j,mv=tmp;
+        }
+    }
+    return printf("%d\n%d %d\n",mv,mi,mj),0;
+}