Using the stack to implement the matching of three parentheses in the string C + + language implementation

write an algorithm that checks the curly brackets in a program, whether the square brackets and parentheses are paired, or 1 if all pairs are returned, otherwise 0.

Head.h:

#ifndef head_h_included

#define Head_h_included

#include <iostream>

struct Linkednode

{

int data;

Linkednode*next;

};

class definition for linkedstack//chain Stacks

{

Public

Linkedstack ();

~linkedstack () {makeempty ();};

void Push (Linkednode &);

int Pop ();

BOOL GetTop (linkednode&x) const;

BOOL IsEmpty () Const{return (top==null)? True:false;}

int getsize () const;

void Makeempty ();

void print ();

Private

Linkednode *top;

};

#endif//head_h_included

Methods.cpp:

#include "Head.h"

#include <iostream>

using namespace Std;

Linkedstack::linkedstack () {top=null;}

void Linkedstack::makeempty ()

{

Linkednode*p;

while (Top!=null)

{

P=top;top=top->next;delete p;

}

}

void Linkedstack::P ush (Linkednode &x)

{

Linkednode *p=top;

x.next=p;

top=&x;

}

int Linkedstack::P op ()

{int data=top->data;

Linkednode*p=top;

top=top->next;

Delete p;

return data;

}

BOOL Linkedstack::gettop (LINKEDNODE&X) const

{

if (IsEmpty () ==true) return false;

X=*top;

return true;

}

int linkedstack::getsize () const

{

int k=0;

Linkednode*p=top;

while (p!=null) {p=p->next;k++;}

return k;

}

void Linkedstack::p rint ()

{

cout<< " number of elements in stack =" <<getsize () <<endl;

Linkednode*p=top;int i=0;

while (P!=null)

{

cout<<++i<< ":" <<p->data<<endl;

p=p->next;

}

}

Main.cpp:

#include "Head.h"

#include <iostream>

#include <string.h>

using namespace Std;

The required algorithm for judging the matching brackets

void Printmatchedpairs (char *expression)

{

Linkedstack S1; Linkedstack S2; Linkedstack S3;

int J,length=strlen (expression);

cout<< " for parentheses () :" <<endl;

for (int i=1;i<=length;i++)

{

if (expression[i-1]== ' (') {Linkednode t;t.data=i;s1. Push (t);} left parenthesis, position into stack

else if (expression[i-1]== ') ')

{

if (S1. IsEmpty () ==false) {j=s1. Pop ();cout<<j<< " and " <<i<< " match " <<ENDL;}

else cout<< " does not have an opening parenthesis that matches the " <<i<< " closing parenthesis !" <<endl;

}

}

while (S1. IsEmpty () ==false)

{

J=s1. Pop ();

cout<< " There is no closing parenthesis that matches the " <<j<< " bracket !" <<endl;

}

cout<< " for brackets [] :" <<endl;

for (int i=1;i<=length;i++)

{

if (expression[i-1]== ' [') {Linkednode t;t.data=i;s2. Push (t);} left parenthesis, position into stack

else if (expression[i-1]== '] ')

{

if (S2. IsEmpty () ==false) {j=s2. Pop ();cout<<j<< " and " <<i<< " match " <<ENDL;}

else cout<< " does not have an opening parenthesis that matches the " <<i<< " closing parenthesis !" <<endl;

}

}

while (S2. IsEmpty () ==false)

{

J=s2. Pop ();

cout<< " There is no closing parenthesis that matches the " <<j<< " bracket !" <<endl;

}

cout<< " for curly braces {} :" <<endl;

for (int i=1;i<=length;i++)

{

if (expression[i-1]== ' {') {Linkednode t;t.data=i;s3. Push (t);} left parenthesis, position into stack

else if (expression[i-1]== '} ')

{

if (S3. IsEmpty () ==false) {j=s3. Pop ();cout<<j<< " and " <<i<< " match " <<ENDL;}

else cout<< " does not have an opening parenthesis that matches the " <<i<< " closing parenthesis !" <<endl;

}

}

while (S3. IsEmpty () ==false)

{

J=s3. Pop ();

cout<< " There is no closing parenthesis that matches the " <<j<< " bracket !" <<endl;

}

}

int main ()

{

Char s[100];

cout<< " Please enter a string with three parentheses to be judged " <<endl;

cin>>s;

Printmatchedpairs (s);

return 0;

}

Operation result :

Using the stack to implement the matching of three parentheses in the string C + + language implementation