PAT basic

#include <stdio.h>
#include <stdlib.h>
#include <iostream>
#include <string>
using namespace std;

string s;

bool func(){
    int i;

    if (s.size()<23)return 0;

    for (i=2;i<=21;i++)
        if(s[i] !='9')return 0;

    while (i<s.size())
        if(s[i++] !='0')return 1;

    return 0;
}

int main(){
   int T; cin>>T;
   while(cin>>s)
    cout<<(func()?"yes":"no")<<"\n";

   return 0;
}


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a+b 2
#include <stdio.h>
int main(){ 
int a,b,n; 
scanf("%d",&n); 
while(n--){  
scanf("%d %d",&a,&b);  
printf("%d\n",a+b); 
}
return 0;
}
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A+B 3 
#include <stdio.h>
int main(){ 
int a,b;
while(scanf("%d %d",&a,&b)!=EOF){ 
if(a==0&b==0)  
break;  
printf("%d\n",a+b); 
} return 0;
}

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A+B 4
#include <stdio.h>
int main(){
int n,x,sum; 
while(scanf("%d",&n)&&n!=0){   
sum=0;  
while(n--){     
scanf("%d",&x);   
sum+=x;  
}   
printf("%d\n",sum); 
}
return 0;
}