CodeForces - 1324D Pair of Topics(二分或双指针)
题意:略题记:做法一:二分#include<bits/stdc++.h>using namespace std;typedef long long ll;const int N=2e5+10;int a[N],b[N],c[N];int main(){ int n; cin>>n; for(int i=1;i<=n;i++) cin>>a[i]; for(int