openjudge-4105-拯救公主-(bfs+)

题目地址

http://bailian.openjudge.cn/practice/4105/

Code

#include <stdio.h>#include <iostream>#include <stdlib.h>#include <string.h>#include <queue>#include <map>#include <vector>#include <math.h>#include <algorithm>#define INF 0x3fffffff#define N 250int dx[4] = {0, 0, 1, -1};int dy[4] = {1, -1, 0, 0};using namespace std;typedef long long LL;struct Node {    int x, y;    int step;    int baoshi;    Node (int xx, int yy, int ss, int bb) {        x = xx;        y  =yy;        step = ss;        baoshi = bb;    }    bool operator < (const Node &b) const {        return step > b.step;    }};int n, m, k;char a[N][N];bool v[N][N][1<<5];bool C(int x, int y) {    if (0 <= x && x < n && 0 <= y && y < m) {        return true;    } else {        return false;    }}int get_baoshi(int x) {    int ans = 0;    while (x > 0) {        ans += (x) & 0x1;        x >>= 1;    }    return ans;}int main() {#ifndef ONLINE_JUDGE    freopen("in", "r", stdin);#else    //#endif    int t;    cin >> t;    for (int i = 0; i < t; i++) {        cin >> n >> m >> k;        memset(a, 0, sizeof(a));        memset(v, 0, sizeof(v));        int sx, sy, ex, ey;        int cx[20];        int cy[20];        int ci = 0;        for (int i = 0; i < n; i++) {            for (int j = 0; j < m; j++) {                cin >> a[i][j];                if (a[i][j] == 'S') {                    sx = i;                    sy = j;                } else if (a[i][j] == 'E') {                    ex = i;                    ey = j;                } else if (a[i][j] == '$') {                    cx[ci] = i;                    cy[ci] = j;                    ci++;                }            }        }        priority_queue<Node> q;        int flag = 0;        q.push(Node(sx, sy, 0, 0));        v[sx][sy][0] = 1;        while(!q.empty()) {            Node cur = q.top();            q.pop();            if (cur.x == ex && cur.y == ey && (get_baoshi(cur.baoshi) >= k)) {                printf("%d\n", cur.step);                flag = 1;                break;            } else if (cur.x == ex && cur.y == ey && (get_baoshi(cur.baoshi) < k)) {                continue;            }            for (int i = 0; i < 4; i++) {;                int nx = cur.x + dx[i];                int ny = cur.y + dy[i];                if (!C(nx, ny)) continue;                if (a[nx][ny] == '#') continue;                int baoshi = cur.baoshi;                if ('0' <= a[nx][ny] && a[nx][ny] <= '4') {                    baoshi |= 1 << (a[nx][ny]-'0');                }                if (v[nx][ny][baoshi]) continue;                v[nx][ny][baoshi] = 1;                if (a[nx][ny] == '$') {                    for (int i = 0; i < ci; i++) {                        nx = cx[i];                        ny = cy[i];                        if (v[nx][ny][baoshi]) continue;                        v[nx][ny][baoshi] = 1;                        q.push(Node(nx, ny, cur.step+1, baoshi));                    }                }                q.push(Node(nx, ny, cur.step+1, baoshi));            }        }        if (flag == 0) {            printf("oop!\n");        }    }    return 0;}