// Here Is a c++ solution of the problem.
#include
using namespace std;
int length(const char* str){
int count =0;
int i =0;
while(str[i]!=‘\0’){
count++;
i++;
}
return count;
}
int main(){
char number[10];
cin >> number;
// cout << number;
if(length(number)==1 and number[0] == ‘0’ ){
cout << 0;
return 0;
}
int test=0;
while(number[test] == ‘0’){
if(test+1==length(number)){
cout << 0;
return 0;
}
test++;
}
if(length(number)%3==0){
for(int j =1; j<=(length(number)); j++){
cout<<number[j-1];
if(j%3==0 and j!=length(number)){
cout << ‘,’;
}
}
}
else if(length(number)%3==1){
for(int j =1; j<=(length(number)); j++){
cout<<number[j-1];
if(j%3==1 and j!=length(number)){
cout << ‘,’;
}
}
}
else if(length(number)%3==2){
for(int j =1; j<=(length(number)); j++){
cout<<number[j-1];
if(j%3==2 and j!=length(number)){
cout << ‘,’;
}
}
}
}