Algorithm/acmicpc.net/source/1935.cpp at master · tdm1223/Algorithm · 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
// 1935. 후위 표기식2
// 2019.08.23
// 자료구조
#include<iostream>
#include<string>
#include<stack>

using namespace std;

int alpa[26];
int main()
{
	int n;
	cin >> n;
	string s;
	cin >> s;

	for (int i = 0; i < n; i++)
	{
		cin >> alpa[i];
	}

	stack<double> stack;
	for (int i = 0; i < s.size(); i++)
	{
		if (s[i] == '+')
		{
			double first = stack.top();
			stack.pop();
			double second = stack.top();
			stack.pop();
			stack.push(first + second);
		}
		else if (s[i] == '-')
		{
			double first = stack.top();
			stack.pop();
			double second = stack.top();
			stack.pop();
			stack.push(second - first);
		}
		else if (s[i] == '*')
		{
			double first = stack.top();
			stack.pop();
			double second = stack.top();
			stack.pop();
			stack.push(first * second);
		}
		else if (s[i] == '/')
		{
			double first = stack.top();
			stack.pop();
			double second = stack.top();
			stack.pop();
			stack.push(second / first);
		}
		else
		{
			stack.push(alpa[s[i]-'A']);
		}
	}
	printf("%.2lf\n", stack.top());
	return 0;
}