2 test cases failing please can you tell whats missing
#include <bits/stdc++.h>
using namespace std;
int main() {
string s;
cin>>s;
for(int i=0;i<s.length();i++){
if(s[i]>='5' && s[0]!='9'){
int num = s[i];
num -= 48;
s[i]=(char)(9-num+48);
}
}
cout<<s;
return 0;
}