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Implement Stack Using Arrays

Problem​

Implement a stack using arrays.

Solution Approach​

Expected Time complexity: O(n)O(n)

Click - to see solution code
class Stack {
    vector<int> v;
    int n;
    int c;

   public:
    Stack(int capacity) {
        v.resize(capacity);
        c = capacity;
        n = 0;
    }

    void push(int num) { v[n++] = num; }

    int pop() {
        if (n == 0) return -1;
        int a = v[--n];
        return a;
    }

    int top() {
        if (n == 0) return -1;
        return v[n - 1];
    }

    int isEmpty() { return (n == 0); }

    int isFull() { return c <= n; }
};