add new problems 9.04

contest/src/main/java/com/github/contest/Execute.kt

@@ -1,7 +1,7 @@
 package com.github.contest
 
 
-import com.github.contest.hashTable.minimumOperations
+import com.github.contest.slidingWindow.minWindowOptimumSolution
 import java.util.TreeMap
 
 
@@ -11,7 +11,9 @@ import java.util.TreeMap
 
 fun main() {
 
-    minimumOperations(intArrayOf(1, 2, 3, 4, 2, 3, 3, 5, 7)).also { println(it) }
+    val s = "ADOBECODEBANC"
+    val t = "ABC"
+    minWindowOptimumSolution(s, t).also { println(it) }
 }
 
 fun testing() {

contest/src/main/java/com/github/contest/slidingWindow/SlidingWindowAlternativeSolution.kt

@@ -0,0 +1,50 @@
+package com.github.contest.slidingWindow
+
+
+/**
+ *
+ */
+
+fun minWindowOptimumSolution(s: String, t: String): String {
+    if (s.isEmpty() || t.isEmpty()) return ""
+
+    val targetMap = mutableMapOf<Char, Int>()
+    for (char in t) {
+        targetMap[char] = targetMap.getOrDefault(char, 0) + 1
+    }
+
+    var left = 0
+    var right = 0
+    var minLength = Int.MAX_VALUE
+    var minStart = 0
+    val required = targetMap.size
+    var formed = 0
+    val windowCounts = mutableMapOf<Char, Int>()
+
+    while (right < s.length) {
+        val char = s[right]
+        windowCounts[char] = windowCounts.getOrDefault(char, 0) + 1
+
+        if (targetMap.containsKey(char) && windowCounts[char] == targetMap[char]) {
+            formed++
+        }
+
+        while (left <= right && formed == required) {
+            if (right - left + 1 < minLength) {
+                minLength = right - left + 1
+                minStart = left
+            }
+
+            val leftChar = s[left]
+            windowCounts[leftChar] = windowCounts.getOrDefault(leftChar, 0) - 1
+            if (targetMap.containsKey(leftChar) && windowCounts[leftChar]!! < targetMap[leftChar]!!) {
+                formed--
+            }
+            left++
+        }
+
+        right++
+    }
+
+    return if (minLength == Int.MAX_VALUE) "" else s.substring(minStart, minStart + minLength)
+}

contest/src/main/java/com/github/contest/slidingWindow/SlidingWindowLeetcode.kt

@@ -1,2 +1,56 @@
 package com.github.contest.slidingWindow
 
+/**
+ * 76. Minimum Window Substring
+ */
+
+fun minWindow(s: String, t: String): String {
+    if (t.length > s.length) return ""
+    val store = mutableMapOf<Char, Int>()
+
+    store.fillMapFromString(t)
+
+    for (k in t.length..s.length) {
+        val cache = mutableMapOf<Char, Int>()
+        var left = 0
+        for (right in s.indices) {
+            val key = s[right]
+            cache[key] = cache.getOrDefault(key, 0) + 1
+            if ((right - left) == (k - 1)) {
+                val isUnique = checkUniqueAnswer(store, cache)
+                if (isUnique) return s.substring(left, right + 1)
+                cache.reduceOrRemove(s[left])
+                left++
+            }
+        }
+    }
+
+    return ""
+}
+
+private fun MutableMap<Char, Int>.fillMapFromString(str: String) {
+    for (char in str) this[char] = this.getOrDefault(char, 0) + 1
+}
+
+private fun MutableMap<Char, Int>.reduceOrRemove(key: Char) {
+    this[key] = this.getOrDefault(key, 0) - 1
+    if (this[key] == 0) this.remove(key)
+}
+
+private fun checkUniqueAnswer(store: MutableMap<Char, Int>, cache: MutableMap<Char, Int>): Boolean {
+    var isUnique = true
+    for ((char, count) in store) {
+        if (cache.contains(char)) {
+            val cacheCount = cache.getOrDefault(char, 0)
+            if (cacheCount < count) {
+                isUnique = false
+                break
+            }
+        } else {
+            isUnique = false
+            break
+        }
+    }
+
+    return isUnique
+}

contest/src/main/java/com/github/contest/slidingWindow/SlidingWindowProdVariant.kt

@@ -0,0 +1,5 @@
+package com.github.contest.slidingWindow
+
+/**
+ *
+ */