gdfz02sjy @ 2023-12-01 18:24:09

#include<bits/stdc++.h>
using namespace std;
long long a,b=0,c=0,d;
int main(){
    cin>>a;
    for(int i=1;i==i;i++){
        for(int j=1;j<i;j++){
            b+=j;
            c++;
            if(c==a){
                cout<<b;
                return 0;
            }
        }
    }
    return 0;
} 

by Cl41Mi5deeD @ 2023-12-01 18:29:53

#include<bits/stdc++.h>
using namespace std;
long long a,b=0,c=0,d;
int main(){
    cin>>a;
    for(int i=1;i==i;i++){
        for(int j=1;j<=i;j++){
            b+=i;
            c++;
            if(c==a){
                cout<<b;
                return 0;
            }
        }
    }
    return 0;
} 

注意审题

by sunyiming0617 @ 2023-12-01 19:06:37

这是一个数学题

#include<bits/stdc++.h> 
using namespace std;
int main(){
    int a,b=0,c=1,i;
    cin>>a;
    for(i=1;i<=a;i++)
        a-=i,b+=c*c,c++;
    cout<<b+a*c;
    return 0;
}

by xxgirlxx @ 2023-12-01 19:19:35

是+i不是+j

by chrisDLkk @ 2023-12-05 15:45:35

}```cpp

include<iostream>

using namespace std; int n;int i=1,ans=0,k=0; int main(){ cin>>n;

while(n>0){
    n-=i;i++;
    k++;
}
//cout<<k<<endl;cout<<(k*(k+1))/2<<endl;
//cout<<n<<endl;
for(int i=1;i<=k;i++){
    ans=ans+i*i;
}
ans=ans+n*(i-1);
cout<<ans<<endl;

return 0;

looook  at   it