java: add «2696. Minimum String Length After Removing Substrings»

Signed-off-by: Matej Focko <me@mfocko.xyz>

java/minimum-string-length-after-removing-substrings.java

@@ -0,0 +1,18 @@
+class Solution {
+  public int minLength(String s) {
+    var st = new Stack<Character>();
+
+    for (var c : s.toCharArray()) {
+      var last = !st.empty() ? st.peek() : '\0';
+      if (last == 'A' && c == 'B') {
+        st.pop();
+      } else if (last == 'C' && c == 'D') {
+        st.pop();
+      } else {
+        st.push(c);
+      }
+    }
+
+    return st.size();
+  }
+}