题解

题解传送门

code

#include <bits/stdc++.h>
using namespace std; 
const int maxn = 1e5 + 100; 
typedef long long LL; 

template <typename T>
inline void read(T &s) {
    s = 0; 
    T w = 1, ch = getchar(); 
    while (!isdigit(ch)) { if (ch == '-') w = -1; ch = getchar(); }
    while (isdigit(ch)) { s = (s << 1) + (s << 3) + (ch ^ 48); ch = getchar(); }
    s *= w; 
}

int n, m; 
int a[maxn];
LL c[2][maxn], sum[maxn]; 

inline int lowbit(int x) { return x & (-x); }

inline void add(int k, int x, int y) {
    for (; x <= n; x += lowbit(x)) 
        c[k][x] += y; 
}

inline LL ask(int k, int x) {
    LL ans = 0ll; 
    for (; x; x -= lowbit(x)) 
        ans += c[k][x]; 

    return ans; 
}

int main() {
    read(n), read(m); 
    for (int i = 1; i <= n; ++i) {
        read(a[i]); 
        sum[i] = sum[i - 1] + a[i]; 
    }

    while (m--) {
        char ch; cin >> ch;  

        if (ch == 'C') {
            int l, r, d; 
            read(l), read(r), read(d); 

            add(0, l, d); 
            add(0, r + 1, -d); 
            add(1, l, l * d); 
            add(1, r + 1, -(r + 1) * d); 
        }
        else if (ch == 'Q') {
            int l, r; 
            read(l), read(r); 

            LL ans = sum[r] + (r + 1) * ask(0, r) - ask(1, r); 
            // check; 
            ans -= sum[l - 1] + l * ask(0, l - 1) - ask(1, l - 1);  

            printf("%lld\n", ans); 
        }
    }
    return 0; 
}