تبدیل میانوندی به پسوندی
#include<stdio.h>
#include<string.h>
#define size 10
char stack[size];
int tos=0,ele;
void push();
char pop();
void show();
int isempty();
int isfull();
char infix[30],output[30];
int prec(char);
//Functions for operations on stack
void push(int ele)
{
stack[tos]=ele;
tos++;
}
char pop()
{
tos--;
return(stack[tos]);
}
void show()
{
int x=tos;
printf("--The Stack elements are.....");
while(x!=0)
printf("%c, ",stack[--x]);
}
//Function to get the precedence of an operator
int prec(char symbol)
{
if(symbol== '(')
return 0;
if(symbol== ')')
return 0;
if(symbol=='+' || symbol=='-')
return 1;
if(symbol=='*' || symbol=='/')
return 2;
if(symbol=='^')
return 3;
return 0;
}
int main()
{
int i=0,j=0,k=0,length;
char temp;
printf("\nEnter an infix expression:");
scanf("%s",infix);
printf("\nThe infix expresson is %s",infix);
length=strlen(infix);
for(i=0;i<length;i++)
{
//Numbers are added to the out put QUE
if(infix[i]!='+' && infix[i]!='-' && infix[i]!='*' && infix[i]!='/' && infix[i]!='^' && infix[i]!=')' && infix[i]!='(' )
{
output[j++]=infix[i];
printf("\nThe element added to Q is:%c",infix[i]);
}
//If an operator or a bracket is encountered...
else
{
if(tos==0) //If there are no elements in the stack, the operator is added to it
{
push(infix[i]);
printf("\nThe pushed element is:%c",infix[i]);
}
else
{ //Operators or pushed or poped based on the order of precedence
if(infix[i]!=')' && infix[i]!='(')
{
if( prec(infix[i]) <= prec(stack[tos-1]) )
{
temp=pop();
printf("\n the poped element is :%c",temp);
output[j++]=temp;
push(infix[i]);
printf("\n The pushed element is :%c",infix[i]);
show();
}
else
{
push(infix[i]);
printf("\nThe pushed element is:%c",infix[i]);
show();
}
}
else
{
if(infix[i]=='(')
{
push(infix[i]);
printf("\nThe pushed-- element is:%c",infix[i]);
}
if(infix[i]==')')
{
temp=pop();
while(temp!='(')
{output[j++]=temp;
printf("\nThe element added to Q is:%c",temp);
//temp=pop();
printf("\n the poped element is :%c",temp);
temp=pop();}
}
}
}
}
printf("\nthe infix expression is: %s",output);
}
while(tos!=0)
{
output[j++]=pop();
}
printf("the infix expression is: %s\n",output);
}
