dsa · medium
Maximum Frequency Stack
GreyOrangeHash MapStackDesign
FreqStack: push(val), pop() removes the most frequent remaining value; ties → the closest to the top of the stack.
Fill in the FreqStack class. The starter already walks ops / args and calls your methods — leave the driver at the bottom as-is. Constructors contribute null; booleans print as true / false.
**Example**
`` FreqStack() → null push(5) → null push(7) → null push(5) → null push(7) → null push(4) → null push(5) → null pop() → 5 pop() → 7 pop() → 5 pop() → 4 ``
Constraints
Calls <= 1000
Examples
Example 1
Input: ["FreqStack","push","push","push","push","push","push","pop","pop","pop","pop"] [[],[5],[7],[5],[7],[4],[5],[],[],[],[]] Expected: [null,null,null,null,null,null,null,5,7,5,4]