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Basic_Of_Algorithm/src/ssafy_avanced_study/no_1248.java

@@ -0,0 +1,80 @@
+package ssafy_avanced_study;
+
+
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.util.Queue;
+import java.util.LinkedList;
+
+public class no_1248 {
+
+
+
+
+	public static void main(String[] args) throws Exception {
+
+
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+		int T;
+		T=Integer.parseInt(br.readLine());
+
+		for(int test_case = 1; test_case <= T; test_case++){
+
+			int size =Integer.parseInt(br.readLine());
+
+			int[][]map = new int[size][size];
+
+			int answer = Integer.MAX_VALUE;
+
+
+			for(int i=0;i<size;i++) {
+				String s = br.readLine();
+				for(int j=0;j<size;j++) {
+					map[i][j] = Integer.parseInt(""+s.charAt(j));
+				}
+			}
+
+			Queue<int[]> q = new LinkedList<>();
+
+			int[][]mov = {{1,0},{0,1},{-1,0},{0,-1}};
+			int[][]temp = new int[size][size];
+			boolean[][]visited = new boolean[size][size];
+			q.add(new int[] {0,0});
+
+			while(!q.isEmpty()) {
+
+				int []c = q.poll();
+				int i = c[0];
+				int j = c[1];
+
+				if(i==size-1 && j==size-1) {
+					answer = Math.min(answer, temp[i][j]);
+					continue;
+				}
+				if(answer<=temp[i][j]) continue;
+
+				for(int d=0;d<4;d++) {
+					int ni = i + mov[d][0];
+					int nj = j + mov[d][1];
+
+					if(ni<0 || nj<0|| size-1 <ni|| size-1 < nj) continue;
+
+					if(!visited[ni][nj] || temp[ni][nj] > temp[i][j] + map[ni][nj]) {
+						visited[ni][nj] = true;
+						temp[ni][nj]  = temp[i][j] + map[ni][nj];
+						q.add(new int[] {ni,nj});	
+					}
+
+				}
+
+			}
+
+			System.out.println("#"+test_case+" "+answer);
+
+
+
+		}
+
+	}
+
+}

Basic_Of_Algorithm/src/ssafy_avanced_study/no_1249.java

@@ -8,7 +8,7 @@
 
 public class no_1249 {
 
-	static int answer = Integer.MAX_VALUE;
+
 
 
 	public static void main(String[] args) throws Exception {
@@ -24,63 +24,57 @@ public static void main(String[] args) throws Exception {
 
 			int[][]map = new int[size][size];
 
-			Queue<int []> q = new LinkedList<>();
-
-			q.add(new int[] {0,0});
+			int answer = Integer.MAX_VALUE;
+
 
 			for(int i=0;i<size;i++) {
-					String str =br.readLine();
+				String s = br.readLine();
 				for(int j=0;j<size;j++) {
-					map[i][j] = Integer.parseInt(""+str.charAt(j));
+					map[i][j] = Integer.parseInt(""+s.charAt(j));
 				}
 			}
 
-
-
+			Queue<int[]> q = new LinkedList<>();
 
+			int[][]mov = {{1,0},{0,1},{-1,0},{0,-1}};
 			int[][]temp = new int[size][size];
-			temp[0][0] = 0;
-
-
-
-
-			dfs(0,0,temp,map,size);
-
-			System.out.println(answer);
-
-		}
-
-
-	}
-	static void dfs(int i,int j,int[][]temp,int[][]map,int size) {
-
-
-		if(map[i][j]>=answer) return;
-
-		int [][] move = {{1,0},{0,1},{-1,0},{0,-1}};
-
-
-		if(i==size-1 && j ==size-1) {
-			answer = Math.min(answer, temp[size-1][size-1]);
-			return;
-		}
-
-		for(int d=0;d<4;d++) {
-
-			int newI = i + move[d][0];
-			int newJ = j + move[d][1];
+			boolean[][]visited = new boolean[size][size];
+			q.add(new int[] {0,0});
 
-			if(newI<0||newJ<0||size-1<newI||size-1<newJ) continue;
+			while(!q.isEmpty()) {
+
+				int []c = q.poll();
+				int i = c[0];
+				int j = c[1];
+
+				if(i==size-1 && j==size-1) {
+					answer = Math.min(answer, temp[i][j]);
+					continue;
+				}
+				if(answer<=temp[i][j]) continue;
+
+				for(int d=0;d<4;d++) {
+					int ni = i + mov[d][0];
+					int nj = j + mov[d][1];
+
+					if(ni<0 || nj<0|| size-1 <ni|| size-1 < nj) continue;
+
+					if(!visited[ni][nj] || temp[ni][nj] > temp[i][j] + map[ni][nj]) {
+						visited[ni][nj] = true;
+						temp[ni][nj]  = temp[i][j] + map[ni][nj];
+						q.add(new int[] {ni,nj});	
+					}
+
+				}
+
+			}
 
+			System.out.println("#"+test_case+" "+answer);
 
-			if(temp[newI][newJ]==0) {
-				temp[newI][newJ] = temp[i][j] + map[newI][newJ];
-				dfs(newI,newJ,temp,map,size);
-				temp[newI][newJ] = 0;
-			}
 
 
 		}
+
 	}
 
 }