#include <stdio.h>
long long int func(int n){
int c;
long long int sum=0;
for(c=1;c<=n;c++){
sum += 2*((c/2)+1) - c;
}
return sum;
}
int main(void) {
int n,i;
long long int sum=0;
for(i=1;i<=n;i++){
sum += func(i);
}
return 0;
}
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