C :

#include<stdio.h>

void main(){
	int i,n,s=0,p;
	scanf("%d",&n);
	
	for(i=1;i<=n;i++){
		p=i*i;
		s=s+p; 
	}
	printf("%d",s); 
		
}

C++ :

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

Java :

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
    Scanner sc=new Scanner(System.in);
    int n=sc.nextInt();
    int i,s=0;
    for(i=1;i<=n;i++) {
    	s=s+i*i;
    }
    System.out.print(s);
    sc.close();
	}

}

Python :

n = int(input())
su = 0
for i in range(1, n + 1):
    su += i * i
print(su)