diff --git a/QUSTOJ/1640.cpp b/QUSTOJ/1640.cpp
new file mode 100644
index 0000000..47c3865
--- /dev/null
+++ b/QUSTOJ/1640.cpp
@@ -0,0 +1,112 @@
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+using namespace std;
+//We have to say this is a mash-up of terrible code. But at least, it solves the problem.
+typedef struct
+{
+    double x,y;
+} point;
+typedef struct
+{
+    double k,b;
+} line_s;
+point inc[3];
+line_s line[3];
+int main()
+{
+    int x,y;
+    int count=0;
+    while(scanf("%lf %lf %lf %lf %lf %lf",&inc[0].x,&inc[0].y,&inc[1].x,&inc[1].y,&inc[2].x,&inc[2].y)==6)
+    {
+        line[0].k=(inc[1].y-inc[0].y)/(inc[1].x-inc[0].x);
+        line[0].b=inc[0].y-line[0].k*inc[0].x;
+        line[1].k=(inc[2].y-inc[1].y)/(inc[2].x-inc[1].x);
+        line[1].b=inc[1].y-line[1].k*inc[1].x;
+        line[2].k=(inc[0].y-inc[2].y)/(inc[0].x-inc[2].x);
+        line[2].b=inc[2].y-line[2].k*inc[2].x;
+        if(!(inc[0].x!=inc[1].x&&inc[1].x!=inc[2].x&&inc[0].x!=inc[2].x))
+        {
+            if(inc[0].x==inc[1].x)
+            {
+                count=0;
+                for(x=1; x<100; x++)
+                {
+                    for(y=1; y<100; y++)
+                    {
+                        if((x-inc[0].x)*(inc[2].x-inc[0].x)>=0)
+                        {
+                            if((y-line[1].k*x-line[1].b)*(inc[0].y-line[1].k*inc[0].x-line[1].b)>=0)
+                            {
+                                if((y-line[2].k*x-line[2].b)*(inc[1].y-line[2].k*inc[1].x-line[2].b)>=0)
+                                {
+                                    count++;
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+            else if(inc[1].x==inc[2].x)
+            {
+                count=0;
+                for(x=1; x<100; x++)
+                {
+                    for(y=1; y<100; y++)
+                    {
+                        if((x-inc[1].x)*(inc[0].x-inc[1].x)>=0)
+                        {
+                            if((y-line[0].k*x-line[0].b)*(inc[2].y-line[0].k*inc[2].x-line[0].b)>=0)
+                            {
+                                if((y-line[2].k*x-line[2].b)*(inc[1].y-line[2].k*inc[1].x-line[2].b)>=0)
+                                {
+                                    count++;
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+            else if(inc[2].x==inc[0].x)
+            {
+                count=0;
+                for(x=1; x<100; x++)
+                {
+                    for(y=1; y<100; y++)
+                    {
+                        if((x-inc[2].x)*(inc[1].x-inc[2].x)>=0)
+                        {
+                            if((y-line[0].k*x-line[0].b)*(inc[2].y-line[0].k*inc[2].x-line[0].b)>=0)
+                            {
+                                if((y-line[1].k*x-line[1].b)*(inc[0].y-line[1].k*inc[0].x-line[1].b)>=0)
+                                {
+                                    count++;
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+            printf("%d\n",count);
+            continue;
+        }
+        count=0;
+        for(x=1; x<100; x++)
+        {
+            for(y=1; y<100; y++)
+            {
+                if((y-line[0].k*x-line[0].b)*(inc[2].y-line[0].k*inc[2].x-line[0].b)>=0)
+                {
+                    if((y-line[1].k*x-line[1].b)*(inc[0].y-line[1].k*inc[0].x-line[1].b)>=0)
+                    {
+                        if((y-line[2].k*x-line[2].b)*(inc[1].y-line[2].k*inc[1].x-line[2].b)>=0)
+                        {
+                            count++;
+                        }
+                    }
+                }
+            }
+        }
+        printf("%d\n",count);
+    }
+}
diff --git a/QUSTOJ/1648.cpp b/QUSTOJ/1648.cpp
new file mode 100644
index 0000000..8a258c9
--- /dev/null
+++ b/QUSTOJ/1648.cpp
@@ -0,0 +1,71 @@
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+using namespace std;
+
+class bign
+{
+public:
+    //WARNING: We use public here to reduce time consumed on Interface, although this is not a recommended way.
+    int data[3000];
+    void set_empty()
+    {
+        memset(data,0,sizeof(int)*3000);
+    }
+    int lenx()
+    {
+        for(int i=3000-1;i>=0;i--)
+        {
+            if(data[i]!=0) return i+1;
+        }
+        return 0;
+    }
+};
+
+bign sum,tmp,a;
+
+char buff[1024];
+
+void ConvertSTRtoBIGN(const char* incstr,bign& incbign)
+{
+    int len=strlen(incstr);
+    for(int i=0;i<len;i++)
+    {
+        incbign.data[len-i-1]=incstr[i]-'0';
+    }
+}
+int main()
+{
+    int times,n;
+    scanf("%d%*c",&times);
+    for(;times>0;times--)
+    {
+        scanf("%d%*c",&n);
+        sum.set_empty();
+        for(;n>0;n--)
+        {
+            gets(buff);
+            tmp.set_empty();
+            ConvertSTRtoBIGN(buff,tmp);
+            int lena=tmp.lenx();
+            int lenb=sum.lenx();
+            int maxlen=(lena>lenb)?(lena):(lenb);
+            for(int i=0;i<maxlen;i++)
+            {
+                sum.data[i]+=tmp.data[i];
+                if(sum.data[i]>9)
+                {
+                    sum.data[i]-=10;
+                    sum.data[i+1]++;
+                }
+            }
+        }
+        int slen=sum.lenx();
+        for(int i=slen-1;i>=0;i--)
+        {
+            printf("%d",sum.data[i]);
+        }
+        printf("\n");
+    }
+    return 0;
+}