[C/C++ 백준 1669번] 댕댕이 쓰다듬기 (Silver 1)

https://www.acmicpc.net/problem/1669

1669번: 멍멍이 쓰다듬기

#include <cstdio>
#include <cmath>
int main(void){
	int X, Y, N, k;
	scanf("%d %d", &X, &Y);
	N = Y - X;
	if(N == 0)
		printf("0");
	else if((int)sqrt(N)==sqrt(N))
		printf("%d",2*(int)sqrt(N)-1);
	else{
		k = (int)sqrt(N);
		if(N <= k*k +k)
			printf("%d",2*k);
		else
			printf("%d",2*k+1);
	}
}