python/TangDou/AcWing/BIT/POJ3468.md

##POJ 3468 A Simple Problem with Integers

#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
const int N = 1000010;
typedef long long LL;

int n, m;
LL a[N];

LL c1[N], c2[N];

#define lowbit(x) (x & -x)

void add(LL c[], LL x, LL v) {
    while (x < N) c[x] += v, x += lowbit(x);
}

LL sum(LL c[], LL x) {
    LL res = 0;
    while (x) res += c[x], x -= lowbit(x);
    return res;
}

LL query(LL x) {
    return sum(c1, x) * (x + 1) - sum(c2, x);
}

int main() {
    scanf("%d%d", &n, &m);
    for (int i = 1; i <= n; i++) {
        scanf("%lld", &a[i]);
        add(c1, i, a[i]), add(c1, i + 1, -a[i]);
        add(c2, i, a[i] * i), add(c2, i + 1, -(i + 1) * a[i]);
    }
    while (m--) {
        char op[110];
        int x, y, k;
        scanf("%s", op);
        if (op[0] == 'Q') {
            scanf("%d%d", &x, &y);
            printf("%lld\n", query(y) - query(x - 1));
        } else {
            scanf("%d%d%d", &x, &y, &k);
            add(c1, x, k), add(c1, y + 1, -k);
            add(c2, x, k * x), add(c2, y + 1, (y + 1) * -k);
        }
    }
    return 0;
}