题解 | #[NOIP2015]金币#

#include <stdio.h>

int main() {
    int d, coin = 0, com = 0;
    scanf("%d", &d);
    int i;
    for (i = 1; i <= d; i++) 
    {
        int j, sum = 0;
        for (j = 1; j <= i; j++) 
        {
            sum += j;
            if (i <= sum) 
            {
                coin = j;
                break;
            }
        }
        com += coin;
    }
    printf("%d\n", com);
    return 0;
}