add js solution for maxProfit IV

Author: jackeyjia

problems/0188.买卖股票的最佳时机IV.md

@@ -230,6 +230,31 @@ class Solution:
 Go：
 
 
+Javascript：
+
+```javascript
+const maxProfit = (k,prices) => {
+    if (prices == null || prices.length < 2 || k == 0) {
+        return 0;
+    }
+    
+    let dp = Array.from(Array(prices.length), () => Array(2*k+1).fill(0));
+
+    for (let j = 1; j < 2 * k; j += 2) {
+        dp[0][j] = 0 - prices[0];
+    }
+    
+    for(let i = 1; i < prices.length; i++) {
+        for (let j = 0; j < 2 * k; j += 2) {
+            dp[i][j+1] = Math.max(dp[i-1][j+1], dp[i-1][j] - prices[i]);
+            dp[i][j+2] = Math.max(dp[i-1][j+2], dp[i-1][j+1] + prices[i]);
+        }
+    }
+
+    return dp[prices.length - 1][2 * k];
+};
+```
+
 
 
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