APPLICATIONS OF STACK CHECKING WELL FORMEDNESS OF PARANTHESIS AIM:
To Write a program for checking Well-Formed of the parenthesis using Linked List

 ALGORITHM:
STEP 1: Start the program
STEP 2: Create the User defined Header file with the Name Stack.h  
STEP 2: Include the Header file with the Main program
STEP 3: Initialize the parameters
STEP 4: Get the Expression
STEP 5: Evaluate the Expression Using Balanced parameters
STEP 6: Stop the program execution.
PROGRAM 1:
Stack.h
#include<iostream.h>
#include<conio.h>
#define size 10
class STK_CLASS
{
private:
struct stack
{
char s[size];
int top;
}st; 
public: 
STK_CLASS(); 
void push(char item); 
int stfull(); 
int stempty(); 
char pop(); 
}; 
STK_CLASS::STK_CLASS() 
{ 
st.top=-1; 
} 
void STK_CLASS::push(char item) 
{ 
st.top++; 
st.s[st.top]=item; 
} 
int STK_CLASS::stempty() 
{ 
if(st.top==-1) 
return 1; 
else 
return 0; 
} 
int STK_CLASS::stfull() 
{ 
if(st.top==size) 
return 1; 
else 

return 0; 
} 
char STK_CLASS::pop() 
{ 
char item; 
item=st.s[st.top]; 
st.top--; 
return(item); 
} 

 PROGRAM2: 
#include<iostream.h> 
#include<conio.h> #include<stdlib.h> #include “stack.h” 
#define size 10 
void main(void) 
{ 
char item; 
char ans,bracket[10]; 
STK_CLASS obj; 
int i; 
clrscr(); 
cout<<”\n\t\t Program for stack application using separate header file”; cout<<”\n Enter the expression and put $ at the end “; 
cin>>bracket; 
i=0; 
if(bracket[i]==’(‘) 
cout<<”\n The expression is invalid”; 
else 
{ 
do 
{ 
while(bracket[i]==’(‘) 
{ 
obj.push(bracket[i]); 
i++; 
} 
while(bracket[i]==’)’) 
{ 
item=obj.pop(); 
i++; 
} 
}while(bracket[i]!=”$”); 
if(obj.stempty()) 
cout<<”\n The expression is invalid”; 
else 
cout<<”\n The expression has well formed paranthesis”; 
} 
getch(); 
} 

 OUTPUT: 
Program for stack application using separate header file. 
Enter the expression and put  $ at the end (()(()))$ 
The expression has well formed paranthesis .