Create 3225_niuox.cpp

From http://blog.csdn.net/niuox/article/details/9664487

POJ/3225_niuox.cpp

@@ -0,0 +1,121 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+using namespace std;
+
+#define Maxn 132000
+
+//宏定义最好全加上括号
+#define lx (x<<1)
+#define rx ((x<<1) | 1)
+#define MID ((l + r)>>1)
+
+int cover[Maxn<<2];
+int XOR[Maxn<<2];
+bool vis[Maxn+5];
+
+void FXOR(int x)
+{
+    if(cover[x]!=-1) cover[x] ^= 1;
+    //注意是else
+    else XOR[x] ^= 1;
+}
+void pushDown(int x)
+{
+    //cover[x] == -1代表x节点的覆盖工作已经结束
+    if(cover[x]!=-1)
+    {
+        cover[lx] = cover[rx] = cover[x];
+        XOR[lx] = XOR[rx] = 0;//既然已经覆盖异或标记就清零
+        cover[x] = -1;
+    }
+    if(XOR[x])
+    {
+        FXOR(lx);
+        FXOR(rx);
+        XOR[x] = 0;
+    }
+}
+
+void update(int L,int R,char op,int l,int r,int x)
+{
+    if(L<=l && r<=R)
+    {
+        if(op == 'U')
+        {
+            cover[x] = 1;
+            XOR[x] = 0;
+        }
+        //op == 'I'的情况，由于L<=l && r<=R，所以不需要讨论
+        else if(op == 'D')
+        {
+            cover[x] = 0;
+            XOR[x] = 0;
+        }
+        else if(op == 'C') FXOR(x);
+        else if(op == 'S') FXOR(x);
+        return;
+    }
+    pushDown(x);
+    if(L<=MID) update(L,R,op,l,MID,lx);
+    else if(op == 'I' || op == 'C') cover[lx] = XOR[lx] = 0;
+    if(MID<R) update(L,R,op,MID+1,r,rx);
+    else if(op == 'I' || op == 'C') cover[rx] = XOR[rx] = 0;
+}
+//只适合于一次查询
+void query(int l,int r,int x)
+{
+    if(cover[x] == 1)
+    {
+        for(int i=l; i<=r; i++) vis[i] = true;
+        return;
+    }
+    else if(cover[x] == 0) return;
+    if(l == r) return;
+    pushDown(x);
+    query(l,MID,lx);
+    query(MID+1,r,rx);
+
+}
+
+int main()
+{
+    #ifndef ONLINE_JUDGE
+    freopen("in.txt","r",stdin);
+    #endif
+    int a,b;
+    char op,lchar,rchar;
+    XOR[1] = cover[1] = 0;
+    while(scanf("%c %c%d,%d%c\n",&op,&lchar,&a,&b,&rchar)!=EOF)
+    {
+        a<<=1;
+        b<<=1;
+        if(lchar == '(') a++;
+        if(rchar == ')') b--;
+        update(a,b,op,0,Maxn,1);
+    }
+    query(0,Maxn,1);
+    int s = -1,e;
+    bool flag = false;
+    for(int i=0;i<=Maxn;i++)
+    {
+        if(vis[i] == 1)
+        {
+            if(s == -1) s = i;
+            e = i;
+        }
+        else
+        {
+            if(s!=-1)
+            {
+                if(flag) printf(" ");
+                printf("%c%d,%d%c",s&1?'(':'[',s>>1,(e+1)>>1,e&1?')':']');
+                s = -1;
+                flag = true;
+            }
+        }
+    }
+    if(!flag) printf("empty set");
+    puts("");
+    return 0;
+}