2023/01/week3 알고리즘

Algorithm/Solution/2023/01/week3/SWS/0070-climbing-stairs.java

@@ -0,0 +1,14 @@
+class Solution {
+
+    public int climbStairs(int n) {
+        int[] dp = new int[46];
+        dp[1] = 1;
+        dp[2] = 2;
+
+        for(int i = 3; i <= n; i++) {
+            dp[i] = dp[i - 1] + dp[i - 2];
+        }
+
+        return dp[n];
+    }
+}

Algorithm/Solution/2023/01/week3/SWS/0168-excel-sheet-column-title.java

@@ -0,0 +1,32 @@
+class Solution {
+    public char convertToAlphabet(int num) {
+        int startAscii = (int)'A' - 1;
+
+        if(num == 0) {
+            return 'Z';
+        }
+
+        return (char)(startAscii + num);
+    } 
+
+    public String convertToTitle(int columnNumber) {
+        // 26진수
+        StringBuilder sb = new StringBuilder();
+
+        while(columnNumber > 26) {
+            int mod = columnNumber % 26;
+            sb.append(convertToAlphabet(mod));
+
+            columnNumber /= 26;
+
+            if(mod == 0) {
+                columnNumber--;
+            }
+
+        }
+
+        sb.append(convertToAlphabet(columnNumber));
+
+        return sb.reverse().toString();
+    }
+}

Algorithm/Solution/2023/01/week3/SWS/그림.java

@@ -0,0 +1,63 @@
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.StringTokenizer;
+
+public class Main {
+	static int[] DIR_ROW = {-1, 1, 0, 0}, DIR_COL = {0, 0, -1, 1}; // 상하좌우
+	static int paintSize;
+	public static void findPaint(int[][] board, int r, int c) {
+		paintSize++;
+		board[r][c] = 0;
+
+		int maxRow = board.length;
+		int maxCol = board[0].length;
+
+		for(int i = 0; i < 4; i++) {
+			int nr = r + DIR_ROW[i];
+			int nc = c + DIR_COL[i];
+
+			if(nr < 0 || nr >= maxRow || nc < 0 ||nc == maxCol || board[nr][nc] == 0) {
+				continue;
+			}
+
+			findPaint(board, nr, nc);
+		}
+
+	}
+
+	public static void main(String[] args) throws IOException {
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+
+		StringTokenizer st = new StringTokenizer(br.readLine());
+
+		int n = Integer.parseInt(st.nextToken());
+		int m = Integer.parseInt(st.nextToken());
+
+		int[][] board = new int[n][m];
+
+		for (int i = 0; i < n; i++) {
+			st = new StringTokenizer(br.readLine());
+
+			for (int j = 0; j < m; j++) {
+				board[i][j] = Integer.parseInt(st.nextToken());
+			}
+		}
+
+		int count = 0;
+		int maxSize = 0;
+
+		for (int i = 0; i < n; i++) {
+			for (int j = 0; j < m; j++) {
+				if(board[i][j] == 1) {
+					count++;
+					paintSize = 0;
+					findPaint(board, i, j);
+					maxSize = Math.max(paintSize, maxSize);
+				}
+			}
+		}
+
+		System.out.println(count + "\n" + maxSize);
+	}
+}

Algorithm/Solution/2023/01/week3/SWS/디펜스 게임.java

@@ -0,0 +1,38 @@
+import java.util.*;
+
+class Solution {
+    public int solution(int n, int k, int[] enemy) {
+        int finalRound = enemy.length;
+
+        if(finalRound <= k) {
+            return finalRound;
+        }    
+
+        PriorityQueue<Integer> pq = new PriorityQueue(Collections.reverseOrder());
+
+        for(int i = 0; i < finalRound; i++) {
+            pq.add(enemy[i]);
+
+            if(n >= enemy[i]) {
+                n -= enemy[i];
+                continue;
+             }
+
+            if(k == 0) {
+                return i;
+            }
+
+            n += pq.poll();
+            k--;
+
+            if(n < enemy[i]) {
+                return i;
+            }
+
+            n -= enemy[i];
+        }
+
+
+        return finalRound;
+    }
+}

Algorithm/Solution/2023/01/week3/SWS/음식물 피하기.java

@@ -0,0 +1,66 @@
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.LinkedList;
+import java.util.Queue;
+import java.util.StringTokenizer;
+
+public class Main {
+	static int[] DIR_ROW = {-1, 1, 0, 0}, DIR_COL = {0, 0, -1, 1}; // 상하좌우
+	static int size;
+
+	public static void findWaste(boolean[][] path, int r, int c) {
+		size++;
+		path[r][c] = false;
+
+		int maxRow = path.length;
+		int maxCol = path[0].length;
+
+		for(int i = 0; i < 4; i++) {
+			int nr = r + DIR_ROW[i];
+			int nc = c + DIR_COL[i];
+
+			if(nr < 0 || nr >= maxRow || nc < 0 ||nc == maxCol || !path[nr][nc]) {
+				continue;
+			}
+
+			findWaste(path, nr, nc);
+		}
+
+	}
+
+	public static void main(String[] args) throws IOException {
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+
+		StringTokenizer st = new StringTokenizer(br.readLine());
+
+		int N = Integer.parseInt(st.nextToken());
+		int M = Integer.parseInt(st.nextToken());
+		int K = Integer.parseInt(st.nextToken());
+
+		boolean[][] path = new boolean[N][M];
+
+		for (int i = 0; i < K; i++) {
+			st = new StringTokenizer(br.readLine());
+
+			int r = Integer.parseInt(st.nextToken()) - 1;
+			int c = Integer.parseInt(st.nextToken()) - 1;
+
+			path[r][c] = true;
+		}
+
+		int maxSize = 0;
+
+		for (int i = 0; i < N; i++) {
+			for (int j = 0; j < M; j++) {
+				if(path[i][j]) {
+					size = 0;
+					findWaste(path, i, j);
+					maxSize = Math.max(size, maxSize);
+				}
+			}
+		}
+
+		System.out.println(maxSize);
+	}
+}

Algorithm/Solution/2023/01/week3/SWS/택배 배달과 수거하기.java

@@ -0,0 +1,27 @@
+class Solution {
+    public long solution(int cap, int n, int[] deliveries, int[] pickups) {
+        long answer = 0;
+
+        int length = deliveries.length;
+        int dBox = 0;
+        int pBox = 0;
+
+        for(int i = length - 1; i >= 0; i--) {
+            int cnt = 0;
+
+            while(dBox <  deliveries[i] || pBox < pickups[i]) {
+                dBox += cap;
+                pBox += cap;
+                cnt++;
+            }
+
+            dBox -= deliveries[i];
+            pBox -= pickups[i];
+
+            answer += (long)((i + 1) * cnt * 2);
+        }
+
+
+        return answer;
+    }
+}