diff --git "a/suyeun84/202502/04 BOJ G4 \355\214\214\354\235\264\355\224\204 \354\230\256\352\270\260\352\270\2602.md" "b/suyeun84/202502/04 BOJ G4 \355\214\214\354\235\264\355\224\204 \354\230\256\352\270\260\352\270\2602.md" new file mode 100644 index 00000000..73ea3787 --- /dev/null +++ "b/suyeun84/202502/04 BOJ G4 \355\214\214\354\235\264\355\224\204 \354\230\256\352\270\260\352\270\2602.md" @@ -0,0 +1,48 @@ +```java +import java.util.*; +import java.io.*; + +class Solution +{ + public static void main(String[] args) throws Exception{ + BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); + StringTokenizer st = new StringTokenizer(br.readLine()); + + int N = Integer.parseInt(st.nextToken()); + long answer = 0; + int[][] board = new int[N][N]; + long[][][] dp = new long[N][N][3]; + for (int i = 0; i < N; i++) { + st = new StringTokenizer(br.readLine()); + for (int j = 0; j < N; j++) { + board[i][j] = Integer.parseInt(st.nextToken()); + } + } + dp[0][1][0] = 1; + if(board[1][2] == 0 && board[0][2] == 0 && board[1][1] == 0) dp[1][2][2] = 1; + for (int i = 2; i < N; i++) { + if(board[0][i] == 0) dp[0][i][0] = dp[0][i-1][0]; + if (i == 2) { + if(board[i][2] == 0) dp[2][2][1] = dp[1][2][2]; + } else { + if(board[i][2] == 0) dp[i][2][1] = dp[i-1][2][1]; + } + } + + for (int i = 1; i < N; i++) { + for (int j = 3; j < N; j++) { + if (board[i][j] == 1) continue; + dp[i][j][0] = dp[i][j-1][0] + dp[i][j-1][2]; + dp[i][j][1] = dp[i-1][j][1] + dp[i-1][j][2]; + if (board[i-1][j] == 0 && board[i][j-1] == 0) + dp[i][j][2] = dp[i-1][j-1][0] + dp[i-1][j-1][1] + dp[i-1][j-1][2]; + } + } + for (int i = 0; i < 3; i++) { + answer += dp[N-1][N-1][i]; + } + System.out.println(answer); + } +} + +```