Untitled

#include<stdio.h> 
#include<string.h> 
char stack[20]; 
int top=-1; 
void push(char); 
char pop() ;
int main() 
{
char str[20], ch ;
int l,i;
printf("Welcome To String Reverse Program by Shakti Biswal \n");
printf("\nEnter String: "); 
gets(str); 
l=strlen(str); 
for(i=0;i<l;i++)
{ 
push(str[i]);
}
printf("\nReversted String: "); 
for(i=0;i<l;i++) 
{
ch=pop(); 
printf("%c",ch); 
}
return 0;
}
void push (char c) 
{
top++; 
stack[top]=c;
}
char pop() 
{
char c ;
c=stack[top]; 
top--;
return c;
}