[이분탐색] 11월 8일

10_이분탐색/14500.cpp

@@ -0,0 +1,87 @@
+//10_이분탐색 필수2: 14500
+
+#include <iostream>
+#include <vector>
+
+using namespace std;
+
+int n, m, ans;
+vector<vector<int>> map;
+vector<vector<bool>> visit;
+vector<int> dy = {-1, 1, 0, 0};
+vector<int> dx = {0, 0, -1, 1};
+
+void dfs(int y, int x, int cnt, int sum, vector<vector<bool>>& visit) 
+{
+    if (cnt >= 4) 
+    {
+        ans = max(ans, sum);
+        return;
+    }
+
+    for (int k = 0; k < 4; k++) 
+    {
+        int ny = y + dy[k];
+        int nx = x + dx[k];
+
+        if (ny < 0 || nx < 0 || ny >= n || nx >= m || visit[ny][nx]) {
+            continue;
+        }
+
+        visit[ny][nx] = true;
+        dfs(ny, nx, cnt + 1, sum + map[ny][nx], visit);
+        visit[ny][nx] = false;
+    }
+}
+
+void check(int y, int x) 
+{
+    if (y < n - 2 && x < m - 1){
+        ans = max(ans, map[y][x] + map[y + 1][x] + map[y + 2][x] + map[y + 1][x + 1]);
+    }
+
+    if (y < n - 2 && x > 0){
+        ans = max(ans, map[y][x] + map[y + 1][x] + map[y + 2][x] + map[y + 1][x - 1]);
+    }
+
+    if (y < n - 1 && x < m - 2){
+        ans = max(ans, map[y][x] + map[y][x + 1] + map[y][x + 2] + map[y + 1][x + 1]);
+    }
+
+    if (y > 0 && x < m - 2){
+        ans = max(ans, map[y][x] + map[y][x + 1] + map[y][x + 2] + map[y - 1][x + 1]);
+    }
+}
+
+int main() 
+{
+    ios::sync_with_stdio(false);
+    cin.tie(NULL);
+
+    cin >> n >> m;
+    map.assign(n, vector<int>(m));
+    visit.assign(n, vector<bool>(m, false));
+
+    for (int i = 0; i < n; i++) 
+    {
+        for (int j = 0; j < m; j++) {
+            cin >> map[i][j];
+        }
+    }
+
+    for (int i = 0; i < n; i++) 
+    {
+        for (int j = 0; j < m; j++) 
+        {
+            visit[i][j] = true;
+            dfs(i, j, 1, map[i][j], visit);
+
+            visit[i][j] = false;
+            check(i, j);
+        }
+    }
+
+    cout << ans << "\n";
+
+    return 0;
+}