倒水问题 隐式图搜索问题

#include <cstdio>
#include <iostream>
#include <algorithm>
#include <queue>
#include <stack>
#include <climits>
#include <cstring>
#include <cmath>
#include <map>
#include <set>

using namespace std;
struct node{
	int x,y;
};
int a,b,tar;
node prestate[1010][1010];
int ope[10101][1010];
int flag[1010][1010];

void print(node cur){
	if(cur.x == 0 && cur.y == 0)
		return;
	int op = ope[cur.x][cur.y];
	node s = prestate[cur.x][cur.y];
	print(s);
	switch(op){
		case 1:{
			printf("fill A\n");
			break;
		}
		case 2:{
			printf("fill B\n");
			break;
		}
		case 3:{
			printf("pour A B\n");
			break;
		}
		case 4:{
			printf("pour B A\n");
			break;
		}
		case 5:{
			printf("empty A\n");
			break;
		}
		case 6:{
			printf("empty B\n");
			break;
		}
	}

}
void bfs(int x,int y){
	node s;
	s.x = x;
	s.y = y;

	queue<node > que;
	que.push(s);

	memset(flag,0,sizeof(flag));

	flag[s.x][s.y] = 1;
	node v;

	int tag = 1;

	while(!que.empty()){
		node tmp = que.front();
		que.pop();

		//fill a
		v.x = a;
		v.y = tmp.y;

		if(!flag[v.x][v.y]){
			que.push(v);
			flag[v.x][v.y] = 1;
			ope[v.x][v.y] = 1;
			prestate[v.x][v.y] = tmp;
		}

		if(v.x == tar || v.y == tar){
			tag = 0;
			break;
		}

		//fill b
		v.x = tmp.x;
		v.y = b;

		if(!flag[v.x][v.y]){
			que.push(v);
			flag[v.x][v.y] = 1;
			ope[v.x][v.y] = 2;
			prestate[v.x][v.y] = tmp;
		}

		if(v.x == tar || v.y == tar){
			tag = 0;
			break;
		}

		// pour a b
		v.x = tmp.x - min(tmp.x,b - tmp.y);
		v.y = tmp.y + min(tmp.x, b - tmp.y);

		if(!flag[v.x][v.y]){
			que.push(v);
			flag[v.x][v.y] = 1;
			ope[v.x][v.y] = 3;
			prestate[v.x][v.y] = tmp;
		}

		if(v.x == tar || v.y == tar){
			tag = 0;
			break;
		}

		//pour b - a

		v.x = tmp.x + min(tmp.y, a - tmp.x);
		v.y = tmp.y - min(tmp.y,a - tmp.x);

		if(!flag[v.x][v.y]){
			que.push(v);
			flag[v.x][v.y] = 1;
			ope[v.x][v.y] = 4;
			prestate[v.x][v.y] = tmp;
		}

		if(v.x == tar || v.y == tar){
			tag = 0;
			break;
		}

		//emp a
		v.x = 0;
		v.y = tmp.y;

		if(!flag[v.x][v.y]){
			que.push(v);
			flag[v.x][v.y] = 1;
			ope[v.x][v.y] = 5;
			prestate[v.x][v.y] = tmp;
		}

		if(v.x == tar || v.y == tar){
			tag = 0;
			break;
		}

		//emp b
		v.x = tmp.x;
		v.y = 0;

		if(!flag[v.x][v.y]){
			que.push(v);
			flag[v.x][v.y] = 1;
			ope[v.x][v.y] = 6;
			prestate[v.x][v.y] = tmp;
		}

		if(v.x == tar || v.y == tar){
			tag = 0;
			break;
		}
	}
	if(!tag){
		print(v);
		printf("success\n");
	}
	else{
		printf("unsuccess\n");
	}

}
int main(){

	while(scanf("%d%d%d",&a,&b,&tar)!=EOF){
		bfs(0,0);
	}
	return 0;
}