[20250404] BOJ / G4 / 파이프 옮기기2 / 신희을

ShinHeeEul/202504/04 BOJ G4 파이프 옮기기2.md

@@ -0,0 +1,86 @@
+```java
+import java.util.*;
+import java.io.*;
+
+class Main {
+
+
+	static int[] di = {0,1,1};
+	static int[] dj = {1,0,1};
+	static boolean[][] map;
+	static int N;
+	public static void main(String args[]) throws Exception {
+
+		N = read();
+
+		map = new boolean[N][N];
+
+		for(int i = 0; i < N; i++) {
+			for(int j = 0; j < N; j++) map[i][j] = read() == 1;
+		}
+
+		long[][][] dp = new long[N][N][3];
+
+		dp[0][1][0] = 1;
+
+		for(int i = 0; i < N; i++) {
+			for(int j = 0; j < N; j++) {
+				int ni = i + 1;
+				int nj = j + 1;
+				// 가로로 놓여있을때
+				if(check(i, nj, true)) dp[i][nj][0] += dp[i][j][0];
+				if(check(ni, nj, false)) dp[ni][nj][2] += dp[i][j][0];
+
+				// 세로로 놓여있을때
+				if(check(ni, j, true)) dp[ni][j][1] += dp[i][j][1];
+				if(check(ni, nj, false)) dp[ni][nj][2] += dp[i][j][1];
+
+				// 대각선으로 놓여있을 때
+				if(check(ni, j, true)) dp[ni][j][1] += dp[i][j][2];
+				if(check(i, nj, true)) dp[i][nj][0] += dp[i][j][2];
+				if(check(ni, nj, false)) dp[ni][nj][2] += dp[i][j][2];
+
+			}
+		}
+
+//		for(int i = 0; i < N; i++) {
+//			for(int j = 0; j < N; j++) {
+//				System.out.print(dp[i][j][0] + "" + dp[i][j][1] + "" + dp[i][j][2] + " ");
+//			}
+//			System.out.println();
+//		}
+//		
+		System.out.println(dp[N-1][N-1][0] + dp[N-1][N-1][1] + dp[N-1][N-1][2]);
+	}
+
+	public static boolean check(int i, int j, boolean b) {
+		if(b)return i >= 0 && j >= 0 && i < N && j < N && !map[i][j];
+		return i >= 0 && j >= 0 && i < N && j < N && !map[i][j] && !map[i-1][j] && !map[i][j-1];
+	}
+
+
+	private static int read() throws Exception {
+	    int c;
+	    int n = 0;
+	    boolean negative = false;
+
+	    while ((c = System.in.read()) <= 32) {
+	        if (c == -1) return -1;
+	    }
+
+	    if (c == '-') {
+	        negative = true;
+	        c = System.in.read();
+	    }
+
+	    do {
+	        n = n * 10 + (c - '0');
+	        c = System.in.read();
+	    } while (c > 32);
+
+	    return negative ? -n : n;
+	}
+
+
+}
+```