SDUT2134数据结构实验之栈四：括号匹配

#include<bits/stdc++.h>using namespace std;void f(char a[]){    char stack[100];    int k=0,f=1;    for(int i=0; a[i]!='\0'; i++)    {        if(a[i]=='('||a[i]=='['||a[i]=='{')            stack[++k]=a[i];        else if(a[i]==')'||a[i]==']'||a[i]=='}')        {            char t=stack[k];            if((t=='('&&a[i]==')')||(t=='['&&a[i]==']')||(t=='{'&&a[i]=='}'))                k--;            else f=0;        }    }    if(k==0&&f==1)        printf("yes\n");    else        printf("no\n");}int main(){    char a[100];    while(gets(a)!=NULL)        f(a);}