[20251112] PGM / LV3 / 순위 / 강신지

Author: ksinji

ksinji/202511/12 PGM 순위.md

@@ -0,0 +1,51 @@
+```java
+import java.util.*;
+
+class Solution {
+    public int solution(int n, int[][] results) {
+        int[][] g = new int[n + 1][n + 1];
+
+        // 이기면 1, 지면 -1, 모르면 0
+        for (int[] r : results) {
+            int win = r[0], lose = r[1];
+
+            g[win][lose] = 1;
+            g[lose][win] = -1;
+        }
+
+        for (int k = 1; k <= n; k++) {
+            for (int i = 1; i <= n; i++) {
+                if (i == k) continue;
+                for (int j = 1; j <= n; j++) {
+                    if (j == i || j == k) continue;
+
+                    if (g[i][k] == 1 && g[k][j] == 1) {
+                        g[i][j] = 1;
+                        g[j][i] = -1;
+                    }
+
+                    else if (g[i][k] == -1 && g[k][j] == -1) {
+                        g[i][j] = -1;
+                        g[j][i] = 1;
+                    }
+                }
+            }
+        }
+
+        int answer = 0;
+        for (int i = 1; i <= n; i++) {
+            boolean know = true;
+            for (int j = 1; j <= n; j++) {
+                if (i == j) continue;
+                if (g[i][j] == 0) { 
+                    know = false;
+                    break;
+                }
+            }
+            if (know) answer++;
+        }
+        
+        return answer;
+    }
+}
+```