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saikatkar · Apr 1, 2022 · b4458cd · b4458cd
1 parent bbe25a1
commit b4458cd
Showing 1 changed file with 31 additions and 0 deletions.
diff --git a/402-remove-k-digits/402-remove-k-digits.java b/402-remove-k-digits/402-remove-k-digits.java
@@ -0,0 +1,31 @@
+class Solution {
+    public String removeKdigits(String num, int k) {
+      Stack<Character> stack = new Stack<>();
+      char[] numArr = num.toCharArray();
+      for (int i = 0; i < numArr.length; i++) {
+          while (!stack.isEmpty() && stack.peek() > numArr[i] && k > 0) {
+              stack.pop();
+              k--;
+          }
+          stack.push(numArr[i]);
+      }
+
+      while (k > 0 && !stack.isEmpty()) {
+          stack.pop();
+          k--;
+      }
+      Stack<Character> tempStack = new Stack<>();
+      while (!stack.isEmpty()) {
+          tempStack.push(stack.pop());
+      }
+      while(!tempStack.isEmpty() && tempStack.peek() == '0') {
+          tempStack.pop();
+      }
+      char [] result = new char[tempStack.size()];
+      int i = 0;  
+      while (!tempStack.isEmpty()) {
+          result[i++] = tempStack.pop();
+      }
+      return result.length == 0 ? "0" : String.valueOf(result); 
+    }
+}