59 lines
1.5 KiB
C++
59 lines
1.5 KiB
C++
#include <bits/stdc++.h>
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using namespace std;
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const int N = 110;
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char a[N][N]; //地图
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struct Node {
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int x;
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int y;
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int step;
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};
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queue<Node> q;
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string S = "LQBS"; //行进路线
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int dx[] = {-1, 0, 1, 0}; //左上右下
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int dy[] = {0, 1, 0, -1};
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int step; //移动步数
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int main() {
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int n, m;
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cin >> n >> m;
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for (int i = 1; i <= n; i++)
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for (int j = 1; j <= m; j++) cin >> a[i][j];
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for (int i = 1; i <= n; i++)
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for (int j = 1; j <= m; j++) {
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if (a[i][j] == 'L') {
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q.push({i, j, 1});
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while (q.size()) {
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auto t = q.front();
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q.pop();
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char c = a[t.x][t.y];
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int pos = S.find(c);
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char next = S[(pos + 1) % 4];
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for (int k = 0; k < 4; k++) {
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int x = t.x + dx[k], y = t.y + dy[k];
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if (x >= 1 && x <= n && y >= 1 && y <= m && a[x][y] == next) {
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q.push({x, y, t.step + 1});
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step = max(step, t.step + 1);
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if (step > 2 * n * m) {
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printf("%d", -1);
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exit(0);
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}
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}
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}
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}
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}
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}
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//记录整数值，然后整除4取商即可
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printf("%d", step / 4);
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return 0;
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}
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/*
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4 4
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BLQB
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BBQS
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SBQL
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QQQQ
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*/ |