Symbols cod coach (fails case #4 & case #5)

Question

it passes all the others but I dont know what the problem is
i thought it was for the output and it has to be a string instead of char array but it was not the problem
https://code.sololearn.com/cuea1tofah3I/#cpp

#include <iostream>
#include <string>
using namespace std;
int main () {
string input ;
int j =0 ;
char temp[30];
getline (cin, input);
for (int i = 0 ; input[i] ; i++ ){
if ((input[i]>='a'&&input[i]<='x')||(input[i]>='A'&& input[i]<='Z')||(input[i]==' ')||(input[i]>'0'&& input[i]<'9')){

temp[j++]=input[i];
}
}
string s ;
temp [j+1]='\0';
for (int k = 0;k<j;k++)
{s=s+temp[k];}

cout<< s ;

return 0 ;
}

Answer 1

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

int main() {
string s;
getline(cin,s);

for(unsigned i=0;i<s.length();i++){
if(isalpha(s[i]) || isdigit(s[i]) || isspace(s[i])){
cout<<s[i];
}
else{
continue;
}
}
return 0;
}
This is a simpler approach and easy for anyone to understand.
I Don't know what is the problem with your code between.

Answer 2

these are secret cases so i dont know more than you

Answer 3

You should add more information about the failure of your test

Answer 4

Could you put the text of this case? :)

Answer 5

I mean, what is the object of your case? What would you do with this code?

Answer 6

it's hidden

Answer 7

It's challenge in code coach if you have mobile app of solo learn you can have access to these