题目链接：区间和
#include <iostream>
#include <vector>
#include <algorithm>using namespace std;typedef pair<int, int> PII;const int N = 300010;int n, m;
int a[N], s[N];
vector<int> alls;
vector<PII> add, query;// 求x离散化之后的结果
int find(int x)
{int l = 0, r = alls.size() - 1;while(l < r){int mid = l + r >> 1;if(alls[mid] >= x) r = mid;else l = mid + 1;}return r + 1;
}int main()
{cin >> n >> m;for(int i = 0; i < n; i++){int x, c;cin >> x >> c;add.push_back({x, c});alls.push_back(x);}for(int i = 0; i < m; i++){int l, r;cin >> l >> r;query.push_back({l, r});alls.push_back(l);alls.push_back(r);}// 去重sort(alls.begin(), alls.end());alls.erase(unique(alls.begin(), alls.end()), alls.end());// 处理插入for(auto item: add){int x = find(item.first);a[x] += item.second;}// 预处理前缀和for(int i = 1; i <= alls.size(); i ++) s[i] = s[i - 1] + a[i];// 处理询问for(auto item: query){int l = find(item.first), r = find(item.second);cout << s[r] - s[l - 1] << endl;}return 0;
}
