View Code of Problem 1001

#include <stdio.h>
#include<algorithm>
#include<string.h>
#include<stdlib.h>
#include<queue>

using namespace std;
int vist[100][100];
int sx,sy;
int dir[8][2]={{1,2},{1,-2},{-1,2},{-1,-2},{2,1},{2,-1},{-2,1},{-2,-1}};
struct node
{
    int x,y;
    int step;
};
bool check(int x,int y)
{
    if(x>8||x<1||y>8||y<1||vist[x][y])
    return 0;
    return 1;
}
int bfs(int x,int y)
{
    node st,ed;
    int i;
    queue<node>q;
    st.x=x;
    st.y=y;
    st.step=0;
    q.push(st);
    while(!q.empty())
    {
        st=q.front();
        q.pop();
        if(st.x==sx&&st.y==sy)
        return st.step;
        for(i=0;i<8;i++)
        {
            ed.x=st.x+dir[i][0];
            ed.y=st.y+dir[i][1];
            if(!check(ed.x,ed.y))
            continue;
            ed.step=st.step+1;
            vist[ed.x][ed.y]=1;
            q.push(ed);
        }
    }
    return 0;
}
int main()
{
    char a[20],a1[20];
    int x2,y2;
    while(scanf("%s%s",a,a1)!=EOF)
    {
        sx=a1[0]-'a'+1;
        sy=a1[1]-'0';
        x2=a[0]-'a'+1;
        y2=a[1]-'0';
        memset(vist,0,sizeof(vist));
        vist[x2][y2]=1;
        int ans=bfs(x2,y2);
        printf("To get from %s to %s takes %d knight moves.\n",a,a1,ans);
    }
    return 0;
}