hdu 1698 线段树成段更新

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=1698

 #include <cstdio>
 #include <cmath>
 #include <algorithm>
 #include <iostream>
 #include <cstring>
 #include <queue>
 #include <vector>

 #define maxn 130050
 #define lson l,mid,u<<1
 #define rson mid+1,r,u<<1|1
 using namespace std;

 const int INF = 0x3f3f3f;

 int seg[maxn<<];
 int pau[maxn<<];

 void Push_UP(int u){
     seg[u] =seg[u<<] + seg[u<<|];
 }
 void Push_Down(int l,int r,int u){
     if(pau[u]){
        int mid = (l + r)/;
        pau[u<<]   = pau[u<<|] = pau[u];
        seg[u<<]   = (mid - l + ) * pau[u];
        seg[u<<|] = (r - mid) * pau[u];
        pau[u] = ;
     }
 }
 void build(int l,int r,int u){
     if(l == r){
         seg[u] = ;
         return;
     }
     int mid = (l + r)/;
     build(lson);
     build(rson);
     Push_UP(u);
 }
 void Update(int L,int R,int num,int l,int r,int u){
     if(L <= l && r <= R){  // 这个地方要注意！！
         pau[u] = num;
         seg[u] = num * (r - l + );
         return;
     }
     Push_Down(l,r,u);
     int mid = (l + r)/;
     if(L <= mid)         Update(L,R,num,lson);
     if(R >  mid)         Update(L,R,num,rson);
     Push_UP(u);
 }

 int main()
 {
     if(freopen("input.txt","r",stdin)== NULL)  {printf("Error\n"); exit();}
     int T;
     cin>>T;
     for(int t=;t<=T;t++){
         int N,Q;
         cin>>N;
         build(,N,);
         cin>>Q;
         memset(pau,,sizeof(pau));
         while(Q--){
             int X,Y,Z;
             scanf("%d%d%d",&X,&Y,&Z);
             Update(X,Y,Z,,N,);
         }
         printf("Case %d: The total value of the hook is %d.\n",t,seg[]);
     }
 }