[dovelet][BFS] 도망간 소를 잡아라 / catch_cow

dovelet    14 단계 BFS

도망간 소를 잡아라 / catch_cow

http://59.23.113.171/30stair/catch_cow/catch_cow.php?pname=catch_cow

#include <stdio.h>
 
int queue[1000000][2];
int visit[1000010];
 
int main(void)
{
    int start, end;
    int N, K;
 
    scanf("%d%d", &N, &K);
 
    if (N == K)    {
        printf("0\n");
        return 0;
    }
    else if (N > K)    {
        printf("%d\n", N - K);
        return 0;
    }
  
    visit[queue[end][0]] = 1;
    queue[end][0] = N;
    queue[end++][1] = 0;
 
    while (start <= end)    {
 
        if (queue[start][0] == K)    {
            printf("%d\n", queue[start][1]);
            return 0;
        }
 
        if (queue[start][0] < K && visit[queue[start][0] * 2] == 0)    {
            visit[queue[start][0] * 2] = 1;
            queue[end][0] = queue[start][0] * 2;
            queue[end++][1] = queue[start][1] + 1;
        }
        if (queue[start][0] + 1 <= K && visit[queue[start][0] + 1] == 0)    {
            visit[queue[start][0] + 1] = 1;
            queue[end][0] = queue[start][0] + 1;
            queue[end++][1] = queue[start][1] + 1;
        }
        if (visit[queue[start][0] - 1] == 0)    {
            queue[end][0] = queue[start][0] - 1;
            queue[end++][1] = queue[start][1] + 1;
        }
 
        start++;
    }
 
    return 0;
}