what is wrong in this code

digit
it
number
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return

#1

#include
using namespace std;
int main()
{
long long int a,c=0;
cin>>a;
if(a==0)
{
cout<<“1”;
}
while(a>0)
{
a=a/10;
c++;
}
if(c>0)
{
cout<<c;
}
return 0;

}