leetcode/min-stack/main.cpp at main · milosz275/leetcode · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
#include <bits/stdc++.h>

using namespace std;

class MinStack
{
private:
    stack<int, deque<int>> s;
    priority_queue<int, vector<int>, greater<int>> q;

public:
    MinStack() : s(), q() {}

    void push(int val)
    {
        s.push(val);
        q.push(val);
    }

    void pop()
    {
        if (s.empty() || q.empty())
        {
            if (s.empty())
                throw runtime_error("min-stack.pop: empty stack");
            else
                throw runtime_error("min-stack.pop: empty priority queue");
            return;
        }
        int el = s.top();
        queue<int> temp;
        while (!q.empty() && q.top() != el)
        {
            temp.push(q.top());
            q.pop();
        }
        if (!q.empty())
        {
            q.pop();
            while (!temp.empty())
            {
                q.push(temp.front());
                temp.pop();
            }
        }
        s.pop();
    }

    int top()
    {
        if (s.empty() || q.empty())
        {
            if (s.empty())
                throw runtime_error("min-stack.top: empty stack");
            else
                throw runtime_error("min-stack.top: empty priority queue");
            return -1;
        }
        return s.top();
    }

    int getMin()
    {
        if (s.empty() || q.empty())
        {
            if (s.empty())
                throw runtime_error("min-stack.getMin: empty stack");
            else
                throw runtime_error("min-stack.getMin: empty priority queue");
        }
        return q.top();
    }
};

/**
 * Your MinStack object will be instantiated and called as such:
 * MinStack* obj = new MinStack();
 * obj->push(val);
 * obj->pop();
 * int param_3 = obj->top();
 * int param_4 = obj->getMin();
 */

int main()
{
    try
    {
        unique_ptr<MinStack> s(make_unique<MinStack>());
        s->push(-2);
        s->push(0);
        s->push(-3);
        cout << "min: " << s->getMin() << '\n';
        s->pop();
        cout << "top: " << s->top() << '\n';
        cout << "min: " << s->getMin() << '\n';
    }
    catch(const std::exception& e)
    {
        cerr << e.what() << '\n';
    }

    return 0;
}