hdu Just a Hook

成段更新，注意延迟标记。

#include <stdio.h>

#define maxn 100050
#define lson l , m , rt *2 
#define rson m+1 , r , rt *2 +1
#define dem int m = (l + r) / 2
int sum[maxn*4];
int col[maxn*4];
int n;
void PushUp(int rt){
sum[rt] = sum[rt*2] + sum[rt*2+1];
}
void PushDown(int rt,int m){
if(col[rt]){
col[rt*2] = col[rt*2+1] = col[rt];
sum[rt*2] = (m - m/2) * col[rt];
sum[rt*2+1] = (m / 2) * col[rt];
col[rt] = 0; 
}
}
void build(int l,int r,int rt){
col[rt] = 0;

if(l == r) {
sum[rt] = 1;
return ;
}
int m = (l + r) / 2;
build(lson);
build(rson);
PushUp(rt);
}
void update(int L,int R,int value,int l,int r,int rt){
if(L <= l && r <= R){
sum[rt] = (r - l + 1) * value;
col[rt] = value;
return ;
}
PushDown(rt,r-l+1);
int m = (l + r) / 2;
if(L <= m) update(L,R,value,lson);
if(R > m)update(L,R,value,rson);
PushUp(rt);
} 
int main()
{
int T,Q,a,b,x;
scanf("%d",&T);
for(int i=1;i<=T;i++)
{
scanf("%d",&n);
build(1,n,1);


scanf("%d",&Q);
while(Q--)
{
scanf("%d%d%d",&a,&b,&x);
update(a,b,x,1,n,1);
}
/*for(int j=1;j<=n*4;j++)
printf("%d ",sum[j]);
*/

printf("Case %d: The total value of the hook is %d.\n",i,sum[1]);



}
}