题目1

#include<iostream>
#define ll long long
#define int long long
using namespace std;
const int N=1e5+100;
ll n;
ll a[N],s[N];
ll ans=0;
signed main(){
    cin>>n;
    for(int i=1; i<=n; i++)cin>>a[i];
    for(int i=1; i<=n; i++){
        ans+=(a[i]*a[i])*(n-1);
        //cout<<ans<<" ";
    }
    for(int i=1; i<=n; i++){
        s[i]=s[i-1]+a[i];
    }
    for(int i=1; i<=n-1; i++){
        ans-=2*(s[n]-s[i])*a[i];
    }
    cout<<ans;
    return 0;
}

题目2

`#include<bits/stdc++.h> using namespace std; long long t; int main(){ cin>>t; for(int i=1;i<=t;i++){ long long n=0,k=0,h=0; cin>>n>>k; long long a=n; while(n>0){ h+=n%3; n/=3; }

	if(k>=h && k<=a){
		if((k-h)%2==0){
			cout<<"Yes"<<endl;
		}else{
			cout<<"No"<<endl;
		}
	}else{
		cout<<"No"<<endl;
	}
	
}
return 0;

}`

做题步骤

我们会在赛后检查代码相似度。