PKU 2000. Gold Coins. AC

#include <stdio.h> int gold(int days) { int i, sum=0, time=0, coin=1; for(i=1; i<=days; i++) { sum+=coin; time++; if(time==coin) { coin++; time=0; } } return sum; } int main() { int n; for(scanf("%d", &n); n; scanf("%d", &n)) printf("%d %d\n", n, gold(n)); return 0; }

열심히 돌리는 게 답이네요