UESTC - 1057 秋实大哥与花 线段树模板题

http://acm.uestc.edu.cn/#/problem/show/1057

题意：给你n个数，q次操作，每次在l,r上加上x并输出此区间的sum

题解：线段树模板，

#define  _CRT_SECURE_NO_WARNINGS

#include<iostream>

#include<stdio.h>

using namespace std;

const int maxn = 1e5 + ;

int a[maxn], n, q, l, r, val;

typedef long long ll;

struct node {

    int l, r;

    long long    sum, lazy;

    void update(long long x) {

        sum += (ll)*(r - l + )*x;

        lazy += x;

    }

}tree[maxn*];

void push_up(int x) {

    tree[x].sum = tree[x << ].sum + tree[x <<  | ].sum;

}

void push_down(int x) {

    int lazyval = tree[x].lazy;

    if (lazyval) {

        tree[x << ].update(lazyval);

        tree[x <<  | ].update(lazyval);

        tree[x].lazy = ;

    }

}

void build(int x, int l, int r) {

    tree[x].l = l; tree[x].r = r;

    tree[x].sum = tree[x].lazy = ;

    if (l == r) {

        tree[x].sum = a[l];

    }

    else {

        int mid = l + r >> ;

        build(x << , l, mid);

        build(x <<  | , mid + , r);

        push_up(x);

    }

}

void update(int x, int l, int r, long long val) {

    int L = tree[x].l, R = tree[x].r;

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

        tree[x].update(val);

    }

    else {

        push_down(x);

        int mid = L + R >> ;

        if (mid >= l)update(x << , l, r, val);

        if (r > mid)update(x <<  | , l, r, val);

        push_up(x);

    }

}

long long query(int x,int l,int r) {

    int L = tree[x].l, R = tree[x].r;

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

        return tree[x].sum;

    }

    else {

        push_down(x);

        long long ans = ;

        int mid = L + R >> ;

        if (mid >= l)ans+=query(x << , l, r);

        if (r > mid)ans += query(x <<  | , l, r);

        push_up(x);

        return ans;

    }

}

int main() {

    cin >> n;

    for (int i = ; i <= n; i++) {

        scanf("%d", &a[i]);

    }

    build(, , n);

    cin >> q;

    for (int i = ; i <=q; i++) {

        scanf("%d%d%d", &l, &r, &val);

        update(,l,r,val);

        printf("%lld\n",query(, l, r));

    }

}