問題描述:
給你一個矩陣,問你從左上角走到右下角最短路徑。
題目鏈接:POJ NO.3984
代碼:
#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstdlib>
#include<cmath>
#include<queue>
#include<stack>
#include<cstring>
#include<string>
#include<vector>
#include<set>
#define INF 0x3f3f3f3f
#define PI 3.1415926
#define MAX 10
using namespace std;
struct node{
int x, y, z;
};
int mp[MAX][MAX];
node foot[MAX][MAX];
int dx[] = {1, 0, -1, 0}, dy[] = {0, 1, 0, -1};
bool visit[MAX][MAX];
int bfs(){
queue<node> que;
que.push((node){
0,0,0
});
while(!que.empty()){
node p = que.front();
que.pop();
if(p.x == 4 && p.y == 4) return p.z;
if(visit[p.x][p.y]) continue;
for(int i = 0; i < 4; i++){
node n;
n.x = p.x + dx[i];
n.y = p.y + dy[i];
n.z = p.z + 1;
if(0 <= n.x && n.x < 5 && 0 <= n.y && n.y < 5){
if(!visit[n.x][n.y] && !mp[n.x][n.y]){
que.push(n);
foot[n.x][n.y].x = p.x;
foot[n.x][n.y].y = p.y;
}
}
}
}
return 0;
}
int main(){
memset(visit, false, sizeof(visit));
for(int i = 0; i < 5; i++)
for(int j = 0; j < 5; j++){
scanf("%d", &mp[i][j]);
}
int len = bfs();
int a = 4, b = 4;
node arr[MAX];
for(int i = 0; i < len; i++){
arr[i].x = foot[a][b].x;
arr[i].y = foot[a][b].y;
a = arr[i].x;
b = arr[i].y;
}
for(int i = len - 1; i >= 0; i--){
printf("(%d, %d)\n", arr[i].x, arr[i].y);
}
printf("(4, 4)\n");
return 0;
}