issue #43 1932

Author: sowon-dev

src/backjoon/_1932.java

@@ -0,0 +1,58 @@
+package backjoon;
+// https://www.acmicpc.net/problem/1932
+
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.io.IOException;
+import java.util.StringTokenizer;
+
+public class _1932 {
+  static int[][] arr; //삼각형이 저장되는 2차원배열
+  static Integer[][] dp;
+  static int N;
+
+  // memory 26600 runtime 260
+  public static void main(String[] args) throws IOException {
+    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+    N = Integer.parseInt(br.readLine());
+    arr = new int[N][N];
+    dp = new Integer[N][N];
+    StringTokenizer st;
+    for (int i = 0; i < N; i++) {
+      st = new StringTokenizer(br.readLine(), " ");
+
+      for (int j = 0; j < i + 1; j++) {
+        arr[i][j] = Integer.parseInt(st.nextToken());
+      }
+    }
+    for (int i = 0; i < N; i++) {
+      dp[N - 1][i] = arr[N - 1][i];
+    }
+
+    System.out.println(func(0, 0));
+  }
+  static int func(int depth, int idx) {
+    // 마지막 행일 경우 현재 위치의 dp값 반환
+    if(depth == N - 1)
+      return dp[depth][idx];
+
+    // 탐색하지 않았던 값일 경우 다음 행의 양쪽 값 비교
+    if (dp[depth][idx] == null) {
+      dp[depth][idx] = Math.max(func(depth + 1, idx), func(depth + 1, idx + 1)) + arr[depth][idx];
+    }
+    return dp[depth][idx];
+
+  }
+}
+/*
+input
+5
+7
+3 8
+8 1 0
+2 7 4 4
+4 5 2 6 5
+
+output
+30
+ */