802. 区间和Acwing

#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
typedef pair<int,int>PII2;
vector<int>q;
vector<PII2>PII,PII1;
const int N=3e5+10;
int el[N];
int vl[N];
int sum[N];
int main(){
    int n,m;
    cin>>n>>m;
      while(n--)
        {
        int x,c;
        cin>>x>>c;
        PII.push_back({x,c});
        q.push_back(x);
        }
    while(m--){
        int l,r;
        cin>>l>>r;
        q.push_back(l);
        q.push_back(r);
        PII1.push_back({l,r});
    }
    sort(q.begin(), q.end());
    q.erase(unique(q.begin(), q.end()), q.end());
    int k=0;//去掉重复元素
    for(auto item : PII){
        int x=item.first;
        int l=0,r=q.size()-1;
        while(l<r){
            int mid=(l+r)/2;
            if(q[mid]>=x)r=mid;
            else
            l=mid+1;
        }
        vl[l+1]+=item.second;
    }
    for(int i=1;i<=q.size();i++){
        sum[i]=sum[i-1]+vl[i];
    }
    int l,r;
    for(auto item : PII1){
        l=0,r=q.size()-1;
        while(l<r){
            int mid=(l+r)/2;
            if(q[mid]>=item.first)r=mid;
            else
            l=mid+1;
        }
        int a=l+1;
        l=0,r=q.size()-1;
        while(l<r){
            int mid=(l+r)/2;
            if(q[mid]>=item.second)r=mid;
            else
            l=mid+1;
        }
        int b=l+1;
        cout<<sum[b]-sum[a-1]<<endl;

    }
    return 0;
}