HDU 1698 Just a Hook 线段树 区间更新 惰性标记

#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
using namespace std;
const int MAX=100005;
int F[4*MAX],Mark[4*MAX]= {0};
void build(int x,int left,int right)
{
    if (left==right)
    {
        F[x]=1;
        return;
    }
    int mid=(left+right)/2;
    build(x*2,left,mid);
    build(x*2+1,mid+1,right);
    F[x]=F[x*2]+F[x*2+1];
}
void change(int x,int left,int right,int L,int R,int num)
{
    if (left>R||rightreturn;
    if (left>=L&&right<=R)
    {
        F[x]=(right-left+1)*num;
        Mark[x]=num;
        return;
    }
    int mid=(left+right)/2;
    if (Mark[x])
    {
        Mark[x*2]=Mark[x*2+1]=Mark[x];
        F[x*2]=(mid-left+1)*Mark[x];
        F[x*2+1]=(right-mid)*Mark[x];
        Mark[x]=0;
    }
    if (L<=mid)
        change(x*2,left,mid,L,R,num);
    if (R>mid)
        change(x*2+1,mid+1,right,L,R,num);
    F[x]=F[x*2]+F[x*2+1];
}
int main()
{
    int T,N,Q,a,b,z;
    scanf("%d",&T);
    for (int cases=1;cases<=T;cases++)
    {
        memset(Mark,0,sizeof(Mark));
        scanf("%d%d",&N,&Q);
        build(1,1,N);
        for (int j=1;j<=Q;j++)
        {
            scanf("%d%d%d",&a,&b,&z);
            change(1,1,N,a,b,z);
        }
        printf("Case %d: The total value of the hook is %d.\n",cases,F[1]);
    }
    return 0;
}