Merge pull request #1278 from AlgorithmWithGod/JHLEE325

[20251031] BOJ / G3 / 괄호 추가하기 / 이준희

Author: ShinHeeEul

JHLEE325/202510/31 BOJ G3 괄호 추가하기.md

@@ -0,0 +1,48 @@
+```java
+import java.io.*;
+import java.util.*;
+
+public class Main {
+    static int N;
+    static ArrayList<Integer> nums = new ArrayList<>();
+    static ArrayList<Character> ops = new ArrayList<>();
+    static int answer = Integer.MIN_VALUE;
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        N = Integer.parseInt(br.readLine());
+        String str = br.readLine();
+
+        for (int i = 0; i < N; i++) {
+            char c = str.charAt(i);
+            if (i % 2 == 0) nums.add(c - '0');
+            else ops.add(c);
+        }
+
+        dfs(0, nums.get(0));
+        System.out.println(answer);
+    }
+
+    static void dfs(int idx, int sum) {
+        if (idx >= ops.size()) {
+            answer = Math.max(answer, sum);
+            return;
+        }
+
+        int cur = calc(sum, ops.get(idx), nums.get(idx + 1));
+        dfs(idx + 1, cur);
+
+        if (idx + 1 < ops.size()) {
+            int next = calc(nums.get(idx + 1), ops.get(idx + 1), nums.get(idx + 2));
+            int cur2 = calc(sum, ops.get(idx), next);
+            dfs(idx + 2, cur2);
+        }
+    }
+
+    static int calc(int a, char op, int b) {
+        if (op == '+') return a + b;
+        else if (op == '-') return a - b;
+        else return a * b;
+    }
+}
+```