infix and postfix code example
Example: infix to postfix program in c++
#include <iostream>
#include<string>
using namespace std;
class Stack{
private:
char A[5];
int Size;
public:
int top;
Stack(){
top=-1;
Size=sizeof(A)/sizeof(char);
}
bool IsFull(){
if(top==Size-1){
return true;
}
else{
return false;
}
}
bool IsEmpty(){
if(top==-1){
return true;
}
else{
return false;
}
}
char peek(){
return A[top];
}
void Push(char val){
if (IsFull()==false){
top++;
A[top]=val;
}
else{
cout<<"\nThe Stack is Full"<<endl;
}
}
char Pop(){
if(IsEmpty()==false){
char temp=A[top];
A[top]='0';
top--;
return temp;
}
else{
return '-1';
}
}
void Show_Stack(){
for(int i=0;i<top+1;i++){
cout<<A[i];
}
}
};
int Search(char A){
string CHAR[]={"([","{)","]}","+-","*/","^$"};
int Size=(sizeof(CHAR)/sizeof(string));
for(int i=0;i<Size;i++){
if(A==CHAR[i][0]){
if(i+i>=6){
return i+i;
}
else{
return i+i+0;
}
}
else if(CHAR[i][1]==A){
if(i+i>=6){
return i+i;
}
else{
return i+i+1;
}
}
}
return -1;
}
void Display(char ch,string vari, Stack &s){
int Size=s.top+1;
cout<<"\n "<<ch<<" ";
s.Show_Stack();
for(int i=0;i<10-Size;i++){
cout<<" ";
}
cout<<vari<<endl;
}
int main(){
Stack STACK;
char temp;
string exp;
cout<<"Enter Your Expression :";
cin>>exp;
string out="";
cout<<"\n\nExpression Stack Postfix\n"<<endl;
for(int i=0;i<exp.size();i++){
temp=exp[i];
int ab=Search(temp);
if (ab!=-1){
if(ab<=5 && ab>=3){
while(Search(STACK.peek())>2){
char val=STACK.Pop();
out=out+val;
Display(temp,out,STACK);
}
STACK.Pop();
Display(temp,out,STACK);
}
else{
if (Search(temp)>=0 && Search(temp)<=2){
STACK.Push(temp);
Display(temp,out,STACK);
}
else if(Search(STACK.peek())<ab){
STACK.Push(temp);
Display(temp,out,STACK);
}
else{
while(Search(STACK.peek())>=ab){
char val=STACK.Pop();
out=out+val;
Display(temp,out,STACK);
}
STACK.Push(temp);
Display(temp,out,STACK);
}
}
}
else{
out=out+temp;
Display(temp,out,STACK);
}
}
while(STACK.IsEmpty()==false){
char val=STACK.Pop();
out=out+val;
Display(temp,out,STACK);
}
cout<<"\n\nFINAL STRING : "<<out<<endl;
}