[20250831] PGM / LV3 / 등굣길 / 김수연

Author: suyeun84

suyeun84/202508/31 PGM LV3 등굣길.md

@@ -0,0 +1,26 @@
+```java
+class Solution {
+    public int solution(int m, int n, int[][] puddles) {
+        int answer = 0;
+        int[][] dp = new int[n+1][m+1];
+        dp[1][1] = 1;
+        for (int[] temp : puddles) {
+            dp[temp[1]][temp[0]] = -1;
+        }
+        for (int i = 1; i < n+1; i++) {
+            for (int j = 1; j < m+1; j++) {
+                if (i == 1 && j == 1) continue;
+                if (dp[i][j] == -1) continue;
+                
+                if (dp[i][j-1] > 0) {
+                    dp[i][j] = (dp[i][j] + dp[i][j-1]) % 1000000007;
+                }
+                if (dp[i-1][j] > 0) {
+                    dp[i][j] = (dp[i][j] + dp[i-1][j]) % 1000000007;
+                }
+            }
+        }
+        return dp[n][m];
+    }
+}
+```