달팽이 문제 - 백준

Basic_Of_Algorithm/src/test/snail.java

@@ -0,0 +1,109 @@
+package test;
+
+import java.io.*;
+
+public class snail {
+
+	public static void main(String[] args) throws IOException {
+
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+		int n = Integer.parseInt(br.readLine());
+		int t = Integer.parseInt(br.readLine());
+		solve1(n,t); // 바깥쪽에서 안쪽
+		solve2(n,t); // 안쪽에서 바깥쪽
+
+	}
+
+	// 바깥쪽에서 안쪽으로 돌기
+	static void solve1(int n, int t) {
+		int[][] map = new int[n][n];
+		int value = n*n;
+		int x=0,y=0;
+		int time=0;
+		int limit =n;
+		while(value>0) {
+			x=time;
+			for(int i=y; i<limit; i++) {
+				map[i][x] = value--;
+			}
+
+			y=limit-1;
+			for(int i=x+1; i<limit; i++) {
+				map[y][i] = value--;
+			}
+
+			x=limit-1;
+			for(int i=y-1; i>=time; i--) {
+				map[i][x] = value--;
+			}
+
+			y=time;
+			for(int i=x-1; i>time; i--) {
+				map[y][i] = value--;
+			}
+			time++;
+			limit--;
+			y=time;
+		}
+
+		StringBuilder sb = new StringBuilder();
+		int tx=0, ty=0;
+		for(int i=0; i<n; i++) {
+			for(int j=0; j<n; j++) {
+				if(t==map[i][j]) {
+					ty=i+1;
+					tx=j+1;
+				}
+				sb.append(map[i][j] +" ");
+			}
+			sb.append("\n");
+		}
+		sb.append(ty+" "+tx);
+		System.out.println(sb.toString());
+	}
+
+	// 안쪽에서 바깥쪽으로 돌기
+	static void solve2(int n, int t){
+		int[][] map = new int[n][n];
+		int value =1;
+
+		int x = n/2, y=n/2;
+
+		int limit =1;
+		while(true) {
+			for(int i=0; i<limit; i++) {
+				map[y--][x] = value++;
+			}
+			if(value-1 == n*n) break;
+			for(int i=0; i<limit; i++) {
+				map[y][x++] = value++;
+			}
+
+			limit++;
+			for(int i=0; i<limit; i++) {
+				map[y++][x] = value++;
+			}
+
+			for(int i=0; i<limit; i++) {
+				map[y][x--] = value++;
+			}
+			limit++;
+		}
+
+		StringBuilder sb = new StringBuilder();
+		int tx=0, ty=0;
+		for(int i=0; i<n; i++) {
+			for(int j=0; j<n; j++) {
+				if(t==map[i][j]) {
+					ty=i+1;
+					tx=j+1;
+				}
+				sb.append(map[i][j] +" ");
+			}
+			sb.append("\n");
+		}
+		sb.append(ty+" "+tx);
+		System.out.println(sb.toString());
+	}
+
+}