Hdu1698Just a Hook线段树区间更新

　　区间更新基础。。不说了，也是照着notonlysuccess的博客撸的。

#include <cstdio>

#include <cstring>

#include <algorithm>

#include <climits>

#include <string>

#include <iostream>

#include <map>

#include <cstdlib>

#include <list>

#include <set>

#include <queue>

#include <stack>



using namespace std;

#define lson l,mid,rt<<1

#define rson mid+1,r,rt<<1|1

int sum[444444];

int color[444444];

void up(int rt)

{

    sum[rt] = sum[rt << 1] + sum[rt << 1 | 1];

}



void down(int rt, int len)

{

    if (color[rt]){

        color[rt << 1] = color[rt << 1 | 1] = color[rt];

        int mid = len / 2;

        sum[rt << 1] = (len - mid) * color[rt];

        sum[rt << 1 | 1] = (mid)*color[rt];

        color[rt] = 0;

    }

}

void build(int l, int r, int rt)

{

    color[rt] = 0;

    if (l == r){

        sum[rt] = 1; return;

    }

    int mid = (l + r) >> 1;

    build(lson);

    build(rson);

    up(rt);

}



void update(int L, int R, int add, int l, int r, int rt)

{

    if (L <= l&&r <= R){

        sum[rt] = (r - l + 1) * add; color[rt] = add;

        return;

    }

    int mid = (l + r) >> 1;

    down(rt, r - l + 1);

    if (L <= mid) update(L, R, add, lson);

    if (R>mid) update(L, R, add, rson);

    up(rt);

}



int main()

{

    int Icase; int tt = 0;

    cin >> Icase;

    int n, m; int a, b, c;

    while (Icase--){

        scanf("%d", &n); build(1, n, 1);

        scanf("%d", &m);

        for (int i = 0; i<m; i++){

            scanf("%d%d%d", &a, &b, &c);

            update(a, b, c, 1, n, 1);

        }

        printf("Case %d: The total value of the hook is ", ++tt);

        printf("%d.\n", sum[1]);

    }

    return 0;

}