Min Stack LeetCode solution in C++

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class MinStack {
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 public:
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  stack<int> stk;
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  stack<int> minstk;
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  MinStack() {
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    // leave empty because we don't need to initialise an object while it being
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    // created
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  }
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  void push(int val) {
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    //---------------Push in original stack------------------------------
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    stk.push(val);
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    //-------Put always minimum element to MIN stack--------------
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    if (minstk.size() == 0)
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      minstk.push(val);
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    else {
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      if (minstk.top() < val)
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        minstk.push(minstk.top());
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      else
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        minstk.push(val);
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    }
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  }
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  void pop() {
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    stk.pop();
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    minstk.pop();
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  }
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  int top() {
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    return stk.top();
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  }
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  int getMin() {
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    return minstk.top();
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  }
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};