forked from shivaylamba/Hacktoberfest
-
Notifications
You must be signed in to change notification settings - Fork 0
/
infixtopostfix.cpp
71 lines (69 loc) · 1.32 KB
/
infixtopostfix.cpp
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
#include<iostream>
#include<stack>
using namespace std;
int precedence(char c)
{
if(c=='^')
return 3;
else
if(c=='*'||c=='%'||c=='/')
return 2;
else
if(c=='+'||c=='-')
return 1;
else
return -1;
}
void expression(string exp)
{
stack<char> s;
int n=exp.length();
string st;
s.push('N');
for(int i=0;i<n;i++)
{
if((exp[i]>='a'&&exp[i]<='z')||(exp[i]>='A'&&exp[i]<='Z'))
st=st+exp[i];
else
if(exp[i]=='(')
s.push(exp[i]);
else
if(exp[i]==')')
{
while(s.top()!='N' && s.top()!='(')
{
char c=s.top();
s.pop();
st=st+c;
}
if(s.top()=='(')
{
char c=s.top();
s.pop();
}
}
else
{
while(s.top()!='N'&&precedence(exp[i])<=precedence(s.top()))
{
char c=s.top();
s.pop();
st=st+c;
}
s.push(exp[i]);
}
}
while(s.top()!='N')
{
char c=s.top();
s.pop();
st=st+c;
}
cout<<st<<endl;
}
int main()
{
string ex="A-(B/C+(D%E*F)/G)*H";
expression(ex);
return 0;
}