HDU 1495 非常可乐
http://acm.hust.edu.cn/vjudge/contest/view.action?cid=103711#problem/M
/*BFS简单题 链接地址: http://acm.hdu.edu.cn/showproblem.php?pid=1495 思路:预处理m < n < s,以后处理方便点 初始状态,m,n杯中可乐体积为0,s杯中体积为s; 然后分六种情况: 1, s 倒 m 2, s 倒 n 3, m 倒 n 4, m 倒 s 5, n 倒 m 6, n 倒 s 直到n,s杯中的可乐能等分(此时m杯中体积为0)为止,若不能等分,则输出 NO */ #include<iostream> #include<algorithm> #include<queue> using namespace std; #define maxn 101 bool visited[maxn][maxn]; int m,n,s,si,sj; struct node { int x,y,all,t; //x,y,all分别表示m,n,s杯中可乐的体积,t表示倒了多少次 }; void BFS(){ queue<node> que; memset(visited,false,sizeof(visited)); node p,q; p.x = 0,p.y = 0,p.t = 0,p.all = s; que.push(p); visited[p.x][p.y] = true; while(!que.empty()){ p = que.front(); que.pop(); if(p.y == p.all && p.y == s/2) { printf("%d\n",p.t); return; } if(p.all+p.x > m) //s倒m { q.x = m,q.y = p.y,q.all = p.all+p.x-m,q.t = p.t+1; if(!visited[q.x][q.y]) que.push(q),visited[q.x][q.y] = true; } else { q.x = p.all+p.x,q.y = p.y,q.all = 0,q.t = p.t+1; if(!visited[q.x][q.y]) que.push(q),visited[q.x][q.y] = true; } if(p.all+p.y > n) //s倒n { q.x = p.x, q.y = n, q.all = p.all+p.y-n,q.t = p.t+1; if(!visited[q.x][q.y]) que.push(q),visited[q.x][q.y] = true; } else { q.x = p.x,q.y = p.all+p.y,q.all = 0,q.t = p.t+1; if(!visited[q.x][q.y]) que.push(q),visited[q.x][q.y] = true; } if(p.x+p.y > n) //m倒n { q.x = p.x+p.y-n,q.y = n,q.all = p.all,q.t = p.t+1; if(!visited[q.x][q.y]) que.push(q),visited[q.x][q.y] = true; } else { q.x = 0,q.y = p.x+p.y,q.all = p.all,q.t = p.t+1; if(!visited[q.x][q.y]) que.push(q),visited[q.x][q.y] = true; } q.all = p.all+p.x,q.x = 0,q.y = p.y,q.t = p.t+1; //m倒s if(!visited[q.x][q.y]) que.push(q),visited[q.x][q.y] = true; if(p.x+p.y > m) { q.y = p.y+p.x-m,q.x = m,q.all = p.all,q.t = p.t+1;//n倒m if(!visited[q.x][q.y]) que.push(q),visited[q.x][q.y] = true; } else { q.x = p.x+p.y,q.y = 0,q.all = p.all,q.t = p.t+1; if(!visited[q.x][q.y]) que.push(q),visited[q.x][q.y] = true; } q.all = p.all+p.y,q.x = p.x,q.y = 0,q.t = p.t+1; //n倒s if(!visited[q.x][q.y]) que.push(q),visited[q.x][q.y] = true; } printf("NO\n"); } int main() { //freopen("1013.txt","r",stdin); while(scanf("%d%d%d",&s,&m,&n) && (s||m||n)) { if(s%2) { printf("NO\n"); continue; } if(m > n) swap(m,n); BFS(); } return 0; }