".C" file is available in downloadable format at :
(Open the link and click on the download arrow on the top right to download the file.)
Given below is the code for "C program for Converting Infix expression to Prefix Expression" :
-----------------------------------------------------------------------------------
#include<stdio.h>
#define size 50
char s[size];
int top=-1;
void strrev(char*);
void push(char elem)
{
s[++top]=elem;
}
char pop()
{
return (s[top--]);
}
int precedence(char elem)
{
switch(elem)
{
case'@':return 0;
case')':return 1;
case'+':
case'-':return 2;
case'*':
case'/':return 3;
}
}
void main()
{
char infix[size],prefix[size],ch,elem;
char* x;
int i=0,l=0;
int k=0;
printf("Enter the expression:\t");
scanf("%s",infix);
push('@');
strrev(infix);
while ((ch=infix[l])!='\0')
{
if (ch=='(')
{
push(ch);
}
else if (ch==')')
{
while(s[top]!=')')
prefix[k++]=pop();
elem=pop();
}
else
{
if(precedence(s[top])<=precedence(ch))
{
push(ch);
}
else
{
while(precedence(s[top])>precedence(ch))
prefix[k++]=pop();
push(ch);
}
}
l++;
}
while(s[top]!='@')
prefix[k++]=pop();
prefix[k]='\0';
strrev(prefix);
strrev(infix);
printf("Given infix expression:\t%s\nConverted Prefix expression:\t%s\n",infix,prefix);
}
void strrev(char *w)
{
int i=0;
while(w[i]!='\0')
{
push(w[i]);
i++;
}
int j=0;
while(w[j]!='\0')
{
w[j]=pop();
j++;
}
}
-----------------------------------------------------------------------------------
No comments:
Post a Comment