题解:http://www.cnblogs.com/forever97/p/3522238.html
#include <cstdio> int main() { int n; while(scanf("%d",&n)!=EOF) printf("%d ",(n*n*n+5*n)/6+1); return 0; }
题解:http://www.cnblogs.com/forever97/p/3522238.html
#include <cstdio> int main() { int n; while(scanf("%d",&n)!=EOF) printf("%d ",(n*n*n+5*n)/6+1); return 0; }