weekly contest 312

Author: ZLBer

README.md

@@ -4,6 +4,7 @@ Record leetcode contest and ideas every week, and encourage yourself to think mo
 
 leetcode url: <https://leetcode.cn/u/cctest/>
 
+* 🐑 [weekly contest 311](src/main/java/weekly/wk311.java)     排序 | 脑筋急转弯 | 前缀和 | 并查集
 * 🐑 [weekly contest 311](src/main/java/weekly/wk311.java)     规律 | 滑动窗口 | 层序遍历 | 字典树
 * 🐑 [weekly contest 310](src/main/java/weekly/wk310.java)     排序、hash表 | 贪心 | 贪心、差分数组 | 线段树+区间最大值
 * 🐼 [weekly contest 309](src/main/java/weekly/wk309.java)     数组 | DP/记忆化搜索 | 滑动窗口 | 双堆

src/main/java/tool/contest.java

@@ -0,0 +1,159 @@
+package tool;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+public class contest {
+
+    int[] help(int[] temp) {
+        int[] ans = new int[temp.length];
+        for (int i = 1; i < temp.length; i++) {
+            if (temp[i] > temp[i - 1]) {
+                ans[i] = 1;
+            } else if (temp[i] < temp[i - 1]) {
+                ans[i] = -1;
+            } else {
+                ans[i] = 0;
+            }
+        }
+        return ans;
+    }
+
+    public int temperatureTrend(int[] temperatureA, int[] temperatureB) {
+        int[] a = help(temperatureA);
+        int[] b = help(temperatureB);
+        int ans = 0;
+        int count = 0;
+        for (int i = 1; i < temperatureA.length; i++) {
+            System.out.println(temperatureA[i] + " " + temperatureB[i]);
+            if (a[i] == b[i]) {
+                count++;
+            } else {
+                count = 0;
+            }
+            ans = Math.max(ans, count);
+        }
+        return ans;
+    }
+
+    public int transportationHub(int[][] path) {
+        int[][] dp = new int[1000 + 1][2];
+        Set<Integer> set = new HashSet<>();
+
+        for (int[] ints : path) {
+            dp[ints[0]][0]++;
+            dp[ints[1]][1]++;
+            set.add(ints[0]);
+            set.add(ints[1]);
+        }
+
+        for (int i = 0; i < dp.length; i++) {
+            if (dp[i][1] == set.size() - 1 && dp[i][0] == 0) {
+                return i;
+            }
+        }
+        return -1;
+
+    }
+
+    public int[][] ballGame(int num, String[] plate) {
+        List<int[]> list = new ArrayList<>();
+        for (int i = 0; i < plate.length; i++) {
+            for (int j = 0; j < plate[i].length(); j++) {
+                if (plate[i].charAt(j) == 'O') {
+                    list.add(new int[]{i, j});
+                }
+            }
+        }
+        int[][] moves = new int[][]{
+                {0, 1}, {0, -1}, {1, 0}, {-1, 0}
+        };
+        int[][][][] v = new int[plate.length][plate[0].length()][3][3];
+
+        List<int[]> temp = new ArrayList<>();
+        for (int i = 0; i < list.size(); i++) {
+            int[] begin = list.get(i);
+            for (int[] move : moves) {
+
+                int[] a = check(true, begin[0], begin[1], move[0], move[1], plate, num, v);
+                if (a != null) {
+                    if ((a[0] == 0 && a[1] == 0) || (a[0] == 0 && a[1] == plate[0].length() - 1) || (a[0] == plate.length - 1 && a[1] == 0) || (a[0] == plate.length - 1 && a[1] == plate[0].length() - 1)) {
+                        continue;
+                    }
+                    temp.add(a);
+                }
+            }
+        }
+        int[][] res = new int[temp.size()][2];
+        for (int i = 0; i < temp.size(); i++) {
+            res[i] = temp.get(i);
+        }
+        return res;
+
+    }
+
+    int[] check(boolean init, int x, int y, int up, int left, String[] plate, int num, int[][][][] visited) {
+
+        if (num < 0) {
+            return null;
+        }
+        if (visited[x][y][up + 1][left + 1]>=num) {
+            return null;
+        }
+        visited[x][y][up + 1][left + 1] = num;
+
+
+        //逆时针
+        if (plate[x].charAt(y) == 'E') {
+            if (up != 0) {
+                if (up > 0) {
+                    left = 1;
+                } else {
+                    left = -1;
+                }
+                up = 0;
+            } else {
+                if (left > 0) {
+                    up = -1;
+                } else {
+                    up = 1;
+                }
+                left = 0;
+            }
+            //顺时针
+        } else if (plate[x].charAt(y) == 'W') {
+            if (up != 0) {
+                if (up > 0) {
+                    left = -1;
+                } else {
+                    left = 1;
+                }
+                up = 0;
+            } else {
+                if (left > 0) {
+                    up = 1;
+                } else {
+                    up = -1;
+                }
+                left = 0;
+            }
+        } else if (!init && plate[x].charAt(y) == 'O') {
+            return null;
+        }
+
+        int nx = x + up;
+        int ny = y + left;
+        if (nx < 0 || nx >= plate.length || ny < 0 || ny >= plate[0].length()) {
+            if (plate[x].charAt(y) == '.') {
+                return new int[]{x, y};
+            } else {
+                return null;
+            }
+        }
+
+        return check(false, nx, ny, up, left, plate, num - 1, visited);
+    }
+
+}