weekly contest 301 82

ZLBer · ZLBer · commit 4dd3675b2d64 · 2022-07-17T10:28:31.000+08:00
diff --git a/README.md b/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 301](src/main/java/weekly/wk301.java)     Greegy |   Hash Table | Two Pointers|Dynamic Programming+Combinatorics
 * ☀️ [weekly contest 300](src/main/java/weekly/wk300.java)     Hash Table | Simulation | DP | DP
 * ☔ [weekly contest 299](src/main/java/weekly/wk299.java)     Array |  DP | DP  | Enumeration + classification discussion
 * ☁️ [weekly contest 298](src/main/java/weekly/wk298.java) 
@@ -17,7 +18,7 @@ leetcode url: <https://leetcode.cn/u/cctest/>
 * 🐶 [weekly contest 290](src/main/java/weekly/wk290.java) 
 * 🐭 [weekly contest 280](src/main/java/weekly/wk289.java) 
 
-
+* 🐹 [biweekly contest 82](src/main/java/weekly/wkb82.java)   DFS | Greedy | Greedy| Monotonic Stack/Union Find
 * 🐹 [biweekly contest 81](src/main/java/weekly/wkb81.java) 
 * 🐰 [biweekly contest 80](src/main/java/weekly/wkb80.java)
 * 🐺 [biweekly contest 79](src/main/java/weekly/wkb79.java)
diff --git a/src/main/java/tool/tool.java b/src/main/java/tool/tool.java
@@ -15,6 +15,22 @@ public int comnination(int m, int n) {
         return (int) ans;
     }
 
+
+    //预处理组合数
+    static final int MOD = (int) 1e9 + 7, MX = (int) 1e4 + 1, MX_K = 14;
+    static int[][] c = new int[MX + MX_K][MX_K + 1]; // 组合数
+
+
+    //预处理组合数
+    static {
+        c[0][0] = 1;
+        for (int i = 1; i < MX + MX_K; ++i) {
+            c[i][0] = 1;
+            for (int j = 1; j <= Math.min(i, MX_K); ++j)
+                c[i][j] = (c[i - 1][j] + c[i - 1][j - 1]) % MOD;
+        }
+    }
+
     long gcd(long a, long b) {
         while (b != 0) {
             long temp = a % b;
@@ -373,6 +389,7 @@ private void modify(SegmentTreeNode root, int index, int value) {
             root.sum = root.left.sum + root.right.sum;
         }
     }
+
     public class SegmentTreeNode {
         public int start, end;
         public int max, min, sum; // You can add additional attributes
diff --git a/src/main/java/weekly/wk301.java b/src/main/java/weekly/wk301.java
@@ -0,0 +1,182 @@
+package weekly;
+
+import java.util.ArrayDeque;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Comparator;
+import java.util.Deque;
+import java.util.List;
+import java.util.PriorityQueue;
+import java.util.TreeSet;
+
+public class wk301 {
+
+    //ranking: 2372 / 7133  丢人 - -
+
+    //简单题，贪心，麻烦的做法，每次取两个最大的比较
+   /* public int fillCups(int[] amount) {
+        int res = 0;
+        PriorityQueue<Integer> priorityQueue = new PriorityQueue<>(Comparator.reverseOrder());
+        for (int i : amount) {
+            if (i != 0)
+                priorityQueue.add(i);
+        }
+
+        while (priorityQueue.size() > 2) {
+            Integer poll = priorityQueue.poll() - 1;
+            Integer poll1 = priorityQueue.poll() - 1;
+            res++;
+            if (poll != 0)
+                priorityQueue.add(poll);
+            if (poll1 != 0)
+                priorityQueue.add(poll1);
+        }
+
+        if (!priorityQueue.isEmpty()) {
+            res += priorityQueue.poll();
+        }
+
+
+        return res;
+    }*/
+
+    //贪心
+    public int fillCups(int[] amount) {
+        Arrays.sort(amount);
+        int x = amount[0], y = amount[1], z = amount[2];
+
+        if (x + y <= z) {
+            return z;
+        } else {
+            int t = (x + y - z);
+            if (t % 2 == 0) {
+                return t / 2 + z;
+            } else {
+                return t / 2 + z + 1;
+            }
+        }
+    }
+
+
+    //中等题，哈希表，注意去重
+    class SmallestInfiniteSet {
+
+        int min = 1;
+
+        TreeSet<Integer> priorityQueue = new TreeSet<>();
+
+        public SmallestInfiniteSet() {
+
+        }
+
+        public int popSmallest() {
+            if (!priorityQueue.isEmpty()) {
+                Integer first = priorityQueue.first();
+                priorityQueue.remove(first);
+                return first;
+            }
+            return min++;
+        }
+
+        public void addBack(int num) {
+            if (num < min) {
+                priorityQueue.add(num);
+            }
+        }
+    }
+
+    //中等题，思维题，双指针
+    static public boolean canChange(String start, String target) {
+        for (int i = 0, j = 0; ; i++, j++) {
+            //跳过空格
+            for (; i < start.length() && start.charAt(i) == '_'; i++) {
+            }
+            for (; j < target.length() && target.charAt(j) == '_'; j++) {
+            }
+            //全部检查完毕
+            if (i == start.length() && j == target.length()) {
+                return true;
+            }
+            //以下情况都不正确：
+            //1.有一个遍历完成
+            //2 . L匹配到R
+            //3. target的L比start的L滞后 target的R比start的R提前
+            if (i == start.length() || j == target.length() || start.charAt(i) != target.charAt(j)
+                    || (start.charAt(i) == 'L' ? i < j : i > j)) {
+                return false;
+            }
+        }
+    }
+
+
+    //直接dp超时
+   /* static public int idealArrays(int n, int maxValue) {
+        int mod = (int) 1e9 + 7;
+        long[] dp = new long[maxValue + 1];
+        for (int i = 1; i <= maxValue; i++) {
+            dp[i] = 1;
+        }
+
+        for (int i = 1; i < n; i++) {
+            long[] ndp = new long[maxValue + 1];
+            for (int j = 1; j <= maxValue; j++) {
+                for (int k = 1; k * j <= maxValue; k++) {
+                    ndp[k * j] += dp[j];
+                    ndp[k * j] %= mod;
+                }
+            }
+            dp = ndp;
+        }
+        long res = 0;
+        for (long l : dp) {
+            res += l;
+            res %= mod;
+        }
+        return (int) res;
+    }*/
+
+    static final int MOD = (int) 1e9 + 7, MX = (int) 1e4 + 1, MX_K = 14;
+    static int[][] c = new int[MX + MX_K][MX_K + 1]; // 组合数
+
+
+    //预处理组合数
+    static {
+        c[0][0] = 1;
+        for (int i = 1; i < MX + MX_K; ++i) {
+            c[i][0] = 1;
+            for (int j = 1; j <= Math.min(i, MX_K); ++j)
+                c[i][j] = (c[i - 1][j] + c[i - 1][j - 1]) % MOD;
+        }
+    }
+
+    //困难题，dp+排列组合，质因数分解，最多有14个质因数(n最大是10000)，
+    public int idealArrays(int n, int maxValue) {
+
+        //f[i][j]表示以i结尾的不同的质因数有j的个数
+        int[][] f = new int[maxValue + 1][MX_K + 1];
+        for (int i = 1; i <= maxValue; i++) {
+            f[i][1] = 1;
+        }
+        for (int j = 0; j <= MX_K; j++) {
+            for (int i = 1; i <= maxValue; i++) {
+                for (int k = 2; k * i <= maxValue; k++) {
+                    f[k * i][j] = (f[k * i][j] + f[i][j - 1]) % MOD;
+                }
+            }
+        }
+        //排列组合，在n-1个位置选择k-1个位置插入质因数(0位置必须放一个质因数)
+        long res = 0;
+        for (int i = 1; i < f.length; i++) {
+            for (int j = 1; j < f[0].length; j++) {
+                res = (res + (long) f[i][j] * c[n - 1][j - 1]) % MOD;
+            }
+        }
+
+        return (int) res;
+    }
+
+    public static void main(String[] args) {
+    }
+
+
+}
diff --git a/src/main/java/weekly/wkb79.java b/src/main/java/weekly/wkb79.java
@@ -130,16 +130,16 @@ public BookMyShow(int n, int m) {
         public int[] gather(int k, int maxRow) {
             int i = index(1, 1, n, maxRow + 1, m - k);
             if (i == 0) return new int[]{}; // 不存在
-            var seats = (int) query_sum(1, 1, n, i, i);
+            int seats = (int) query_sum(1, 1, n, i, i);
             add(1, 1, n, i, k); // 占据 k 个座位
             return new int[]{i - 1, seats};
         }
 
         public boolean scatter(int k, int maxRow) {
             if ((long) (maxRow + 1) * m - query_sum(1, 1, n, 1, maxRow + 1) < k) return false; // 剩余座位不足 k 个
             // 从第一个没有坐满的排开始占座
-            for (var i = index(1, 1, n, maxRow + 1, m - 1); ; ++i) {
-                var left_seats = m - (int) query_sum(1, 1, n, i, i);
+            for (int i = index(1, 1, n, maxRow + 1, m - 1); ; ++i) {
+                int left_seats = m - (int) query_sum(1, 1, n, i, i);
                 if (k <= left_seats) { // 剩余人数不够坐后面的排
                     add(1, 1, n, i, k);
                     return true;
@@ -156,7 +156,7 @@ void add(int o, int l, int r, int idx, int val) {
                 sum[o] += val;
                 return;
             }
-            var m = (l + r) / 2;
+            int m = (l + r) / 2;
             if (idx <= m) add(o * 2, l, m, idx, val);
             else add(o * 2 + 1, m + 1, r, idx, val);
             //更新改点的最小值和sum
@@ -167,8 +167,8 @@ void add(int o, int l, int r, int idx, int val) {
         // 返回区间 [L,R] 内的元素和
         long query_sum(int o, int l, int r, int L, int R) { // L 和 R 在整个递归过程中均不变，将其大写，视作常量
             if (L <= l && r <= R) return sum[o];
-            var sum = 0L;
-            var m = (l + r) / 2;
+            long sum = 0L;
+            int m = (l + r) / 2;
             if (L <= m) sum += query_sum(o * 2, l, m, L, R);
             if (R > m) sum += query_sum(o * 2 + 1, m + 1, r, L, R);
             return sum;
@@ -179,7 +179,7 @@ long query_sum(int o, int l, int r, int L, int R) { // L 和 R 在整个递归
         int index(int o, int l, int r, int R, int val) { // R 在整个递归过程中均不变，将其大写，视作常量
             if (min[o] > val) return 0; // 说明整个区间的元素值都大于 val
             if (l == r) return l;
-            var m = (l + r) / 2;
+            int m = (l + r) / 2;
             if (min[o * 2] <= val) return index(o * 2, l, m, R, val); // 看看左半部分
             if (m < R) return index(o * 2 + 1, m + 1, r, R, val); // 看看右半部分
             return 0;
diff --git a/src/main/java/weekly/wkb82.java b/src/main/java/weekly/wkb82.java
