Merge branch 'week4'

Author: spring0913

Diff for: README.md

@@ -20,3 +20,13 @@
 | [요세푸스 문제 0](https://www.acmicpc.net/problem/11866) | [BOJ11866.java](https://github.com/java-algorithm/bom/commit/e1f5552b1db29c4c8c6e3172c8d2aa6e616b4320) |
 | [트럭](https://www.acmicpc.net/problem/13335)        | [BOJ13335.java](https://github.com/java-algorithm/bom/commit/1b6db9953e841d1f262ae2bd753ee77d1d818012) |
 | [마인크래프트](https://www.acmicpc.net/problem/18111)    | [BOJ18111.java](https://github.com/java-algorithm/bom/commit/511de0c38cd73787c4e02780bad8668b24afd7b1) |
+
+## 3주차 BFS/DFS
+| 문제                                                 | 풀이                                                                                                     |
+|----------------------------------------------------|--------------------------------------------------------------------------------------------------------|
+| [안전 영역](https://www.acmicpc.net/problem/2468)      | [BOJ2468.java](https://github.com/java-algorithm/bom/commit/9a2e2a4988ae917a5acc360b9deee8b5d4c3a064)  |
+| [스타트링크](https://www.acmicpc.net/problem/5014)      | [BOJ5014.java](https://github.com/java-algorithm/bom/commit/c768a6682dde154e31e120f0fb90b3a700bf5027)  |
+| [경로 찾기](https://www.acmicpc.net/problem/11403)     | [BOJ11403.java](https://github.com/java-algorithm/bom/commit/0e12aaf73bc283a0df77a5596400641b1a1afb3a) |
+| [트리의 부모 찾기](https://www.acmicpc.net/problem/11725) | [BOJ11725.java](https://github.com/java-algorithm/bom/commit/ddf2a95cf27270655d5ee86f4bf989e8a4c27058) |
+| [데스 나이트](https://www.acmicpc.net/problem/16948)    | [BOJ16948.java](https://github.com/java-algorithm/bom/commit/fb7409184d603887746eb8f446d61444f24509a9) |
+| [아기 상어 2](https://www.acmicpc.net/problem/17086)   | [BOJ17086.java](https://github.com/java-algorithm/bom/commit/c178c31cef1cc4164442d8e6910512ae2b24f7ee) |

Diff for: week4/BOJ_10989(수 정렬하기 3).java

@@ -0,0 +1,29 @@
+import java.io.*;
+
+public class Main {
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        int N = Integer.parseInt(br.readLine());
+        int[] arr = new int[N];
+        int[] count = new int[10002];
+        int[] sortedArr = new int[N];
+        for(int i=0; i<N; i++) {
+            arr[i] = Integer.parseInt(br.readLine());
+            count[arr[i]]++;
+        }
+        for(int i=1; i<=10000; i++) {
+            count[i] += count[i-1];
+        }
+        for(int i=0; i<N; i++) {
+            int n = arr[i];
+            count[n]--;
+            sortedArr[count[n]] = n;
+        }
+        StringBuffer sb = new StringBuffer();
+        for(int i=0; i<N; i++) {
+            sb.append(sortedArr[i]).append('\n');
+        }
+        System.out.print(sb);
+    }
+}

Diff for: week4/BOJ_1141(접두사).java

@@ -0,0 +1,22 @@
+import java.io.*;
+import java.util.*;
+
+public class Main {
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        int N = Integer.parseInt(br.readLine());
+        String[] str = new String[N];
+        for(int i=0; i<N; i++) {
+            str[i] = br.readLine();
+        }
+        Arrays.sort(str);
+        int answer = 1;
+        for(int i=0; i<N-1; i++) {
+            if(!str[i+1].startsWith(str[i])) {
+                answer++;
+            }
+        }
+        System.out.println(answer);
+    }
+}

Diff for: week4/BOJ_1744(수 묶기).java

@@ -0,0 +1,47 @@
+import java.io.*;
+import java.util.*;
+
+public class Main {
+
+    public static void main(String[] args) throws IOException {
+
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        int N = Integer.parseInt(br.readLine());
+        List<Integer> positiveNum = new ArrayList<>();
+        List<Integer> negativeNum = new ArrayList<>();
+        for(int i=0; i<N; i++) {
+            int num = Integer.parseInt(br.readLine());
+            if(num > 0) {
+                positiveNum.add(num);
+            }else {
+                negativeNum.add(num);
+            }
+        }
+        Collections.sort(positiveNum);
+        Collections.sort(negativeNum, Collections.reverseOrder());
+        int answer = getMaxBindSum(positiveNum) + getMaxBindSum(negativeNum);
+        System.out.println(answer);
+    }
+
+    public static int getMaxBindSum(List<Integer> list) {
+        int max = 0;
+        for (int i = list.size()-1; i >= 0; ) {
+            if (i == 0) {
+                max += list.get(i);
+                break;
+            }
+            int multiply = list.get(i) * list.get(i-1);
+            int plus = list.get(i) + list.get(i-1);
+            if (multiply < list.get(i)) {
+                max += list.get(i--);
+            } else if (multiply < plus) {
+                max += plus;
+                i -= 2;
+            } else {
+                max += multiply;
+                i -= 2;
+            }
+        }
+        return max;
+    }
+}

Diff for: week4/BOJ_18870(좌표 압축).java

@@ -0,0 +1,28 @@
+import java.io.*;
+import java.util.*;
+
+public class Main {
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        int N = Integer.parseInt(br.readLine());
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        int[] arr = new int[N];
+        Set<Integer> set = new HashSet<>();
+        for(int i=0; i<N; i++) {
+            arr[i] = Integer.parseInt(st.nextToken());
+            set.add(arr[i]);
+        }
+        List<Integer> list = new ArrayList<>(set);
+        Collections.sort(list);
+        Map<Integer, Integer> map = new HashMap<>();
+        for(int i=0; i<list.size(); i++) {
+            map.put(list.get(i), i);
+        }
+        StringBuffer sb = new StringBuffer();
+        for(int i=0; i<N; i++) {
+            sb.append(map.get(arr[i])).append(' ');
+        }
+        System.out.println(sb);
+    }
+}

Diff for: week4/BOJ_2075(N번째 큰 수).java

@@ -0,0 +1,22 @@
+import java.io.*;
+import java.util.*;
+
+public class Main {
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        int N = Integer.parseInt(br.readLine());
+        PriorityQueue<Integer> q = new PriorityQueue<>((o1, o2) -> o2 - o1);
+        for(int i=0; i<N; i++) {
+            StringTokenizer st = new StringTokenizer(br.readLine());
+            for(int j=0; j<N; j++) {
+                int num = Integer.parseInt(st.nextToken());
+                q.offer(num);
+            }
+        }
+        for(int i=0; i<N-1; i++) {
+            q.poll();
+        }
+        System.out.println(q.peek());
+    }
+}

Diff for: week4/BOJ_2473(세 용액).java

@@ -0,0 +1,49 @@
+import java.io.*;
+import java.util.*;
+
+public class Main {
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        int N = Integer.parseInt(br.readLine());
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        long[] arr = new long[N];
+        for (int i = 0; i < N; i++) {
+            arr[i] = Long.parseLong(st.nextToken());
+        }
+        Arrays.sort(arr);
+        long minAbs = Math.abs(arr[0] + arr[1] + arr[2]);
+        long[] answer = new long[]{arr[0], arr[1], arr[2]};
+        for (int i = 0; i < N - 2; i++) {
+            long[] result = twoPointer(arr, i);
+            long resultAbs = Math.abs(result[0] + result[1] + result[2]);
+            if (minAbs > resultAbs) {
+                minAbs = resultAbs;
+                answer = result.clone();
+            }
+        }
+        System.out.println(answer[0] + " " + answer[1] + " " + answer[2]);
+    }
+
+    public static long[] twoPointer(long[] arr, int index) {
+        int left = index + 1;
+        int right = arr.length - 1;
+        int leftIndex = left;
+        int rightIndex = right;
+        long minAbs = Math.abs(arr[left] + arr[right] + arr[index]);
+        while (left < right) {
+            long sum = arr[index] + arr[left] + arr[right];
+            if (minAbs > Math.abs(sum)) {
+                minAbs = Math.abs(sum);
+                leftIndex = left;
+                rightIndex = right;
+            }
+            if (sum > 0) {
+                right--;
+            } else {
+                left++;
+            }
+        }
+        return new long[]{arr[index], arr[leftIndex], arr[rightIndex]};
+    }
+}

Diff for: week4/BOJ_3758(KCPC).java

@@ -0,0 +1,74 @@
+import java.io.*;
+import java.util.*;
+
+public class Main {
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringBuffer sb = new StringBuffer();
+        int T = Integer.parseInt(br.readLine());
+        for(int i=0; i<T; i++) {
+            StringTokenizer st = new StringTokenizer(br.readLine());
+            int totalTeam = Integer.parseInt(st.nextToken());
+            int totalQuiz = Integer.parseInt(st.nextToken());
+            int teamId = Integer.parseInt(st.nextToken());
+            int logCount = Integer.parseInt(st.nextToken());
+
+            int[][] score = new int[totalTeam+1][totalQuiz+1];
+            int[] submission = new int[totalTeam+1];
+            int[] lastTime = new int[totalTeam+1];
+            Arrays.fill(lastTime, logCount);
+            List<Team> teamList = new ArrayList<>();
+            for(int j=0; j<logCount; j++) {
+                st = new StringTokenizer(br.readLine());
+                int t = Integer.parseInt(st.nextToken());
+                int q = Integer.parseInt(st.nextToken());
+                int s = Integer.parseInt(st.nextToken());
+                score[t][q] = Math.max(score[t][q], s);
+                submission[t]++;
+                lastTime[t] = j;
+            }
+            for(int j=1; j<=totalTeam; j++) {
+                int totalScore = 0;
+                for(int k=1; k<=totalQuiz; k++) {
+                    totalScore += score[j][k];
+                }
+                teamList.add(new Team(j, totalScore, submission[j], lastTime[j]));
+            }
+            Collections.sort(teamList);
+
+            for(int j=0; j<totalTeam; j++) {
+                if(teamId == teamList.get(j).teamId) {
+                    sb.append(j+1).append('\n');
+                    break;
+                }
+            }
+        }
+        System.out.print(sb);
+    }
+
+    public static class Team implements Comparable<Team>{
+        int teamId;
+        int score;
+        int submissionCount;
+        int lastTime;
+
+        public Team(int teamId, int score, int count, int time) {
+            this.teamId = teamId;
+            this.score = score;
+            this.submissionCount = count;
+            this.lastTime = time;
+        }
+
+        @Override
+        public int compareTo(Team t) {
+            if(this.score == t.score) {
+                if(t.submissionCount == this.submissionCount) {
+                    return Integer.compare(this.lastTime, t.lastTime);
+                }
+                return Integer.compare(this.submissionCount, t.submissionCount);
+            }
+            return Integer.compare(t.score, this.score);
+        }
+    }
+}