'commit'

TangDou/Bfs/4_LQBS.cpp

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