Design a Stack With Increment Operation LeetCode solution in Java

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class CustomStack {
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  int[] stack;
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  int top;
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  public CustomStack(int maxSize) {
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    // intialise the stack and the top
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    stack = new int[maxSize];
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    top = -1;
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  }
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  public void push(int x) {
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    // if the stack is full just skip
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    if (top == stack.length - 1) return;
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    // add to the stack
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    top++;
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    stack[top] = x;
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  }
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  public int pop() {
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    // if stack is empty return -1
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    if (top == -1) return -1;
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    // remove/pop the top element
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    top--;
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    return stack[top + 1];
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  }
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  public void increment(int k, int val) {
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    // got to increment the min of the elements present in the stack and k
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    int n = Math.min(top + 1, k);
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    for (int i = 0; i < n; i++) {
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      stack[i] += val;
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    }
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  }
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}