题解 | #[NOIP2015]金币#
[NOIP2015]金币
https://www.nowcoder.com/practice/8f71f5670e6a45118d24d13868a2da9e
#include <stdio.h>
int main() {
int n, i = 1;
int sum = 0, a = 0;
scanf("%d", &n);
while (1)
{
a += i;
if (a < n)
{
sum += i * i;
}
else if (a == n)
{
sum += i * i;
break;
}
else {
sum += i*(i- (a - n));
break;
}
i++;
}
printf("%d", sum);
return 0;
}
