#include "stdio.h"
#include "stdlib.h"
 
typedef struct node{
    char ch;
    node *next;
}Linkstack;

Linkstack *Setstack(){
    Linkstack *S;
    S=(Linkstack*)malloc(sizeof(Linkstack));
    S->next=NULL;
    return S;
}

Linkstack *Pushstack(Linkstack *S,char c){
    Linkstack *p;
    p=(Linkstack*)malloc(sizeof(Linkstack));
    p->ch=c;
    p->next=S->next;
    S->next=p;
    return S;
}

Linkstack *Popstack(Linkstack *S){
    Linkstack *p;
    p=S->next;
    S->next=p->next;
    free(p);
    return S;
}

char Gettop(Linkstack *S){
    if(S->next!=NULL)
    return S->next->ch;
    else
    return ' ';
}

int Judgepair(){
    Linkstack *p;
    char c;
    int sign=1;
    p=Setstack();
    printf("请输入算术表达式，并以'#'结束\n");
    c=getchar();
    while(c!='#'){
        switch(c){
            case'(':
                p=Pushstack(p,c);
                break;
            case')':
                if(Gettop(p)=='(')
                p=Popstack(p);
                else
                sign=0;
                break;
        }
        if(sign==0)
        break;
        else
        c=getchar();
    }
    if(p->next!=NULL)
    sign=0;
    return sign;
}

void Judgeout(int a){
    if(a==1)
    printf("算术表达式小括号配对正确!\n");
    if(a==0)
    printf("算术表达式小括号配对错误!\n");
}

void main(){
    Judgeout(Judgepair());
}

76    11    C:\Users\VULCAN\Desktop\1.cpp    [Error] '::main' must return 'int'