题解 | #[NOIP2015]金币#
[NOIP2015]金币
https://www.nowcoder.com/practice/8f71f5670e6a45118d24d13868a2da9e
#include <stdio.h> int main() { int a = 0; scanf("%d", &a); int i = 0, sum = 0; for (a; a > 0; a = a - i) {//a在不是一个刚好的sum天时,会减成一个负值 sum += i * i; i++; } sum += (i * (a + i));//这里弥补不是正好的情况 printf("%d", sum); return 0; }