How do I remove comma after last number/output loop in C++ - c++

Question

My Code:
#include <iostream>
using namespace std;
void result(int test)
{
for (int num = 1; num <= test; num++)
{
if (num % 3 == 0 && num % 5 == 0)
cout << "extra";
else if (num % 3 == 0 )
cout << "love ";
else if(num %5 == 0)
cout << "extraextra";
else
cout << num;
cout << ",";
}
}
int main()
{
int test = 100;
result(test);
return 0;
}
My Output:
1,2,love ,4,extraextra,love ,7,8,love ,extraextra,11,love ,13,14,extra,16,17,love ,19,extraextra,love ,22,23,love ,extraextra,26,love ,28,29,extra,31,32,love ,34,extraextra,love ,37,38,love ,extraextra,41,love ,43,44,extra,46,47,love ,49,extraextra,love ,52,53,love ,extraextra,56,love ,58,59,extra,61,62,love ,64,extraextra,love ,67,68,love ,extraextra,71,love ,73,74,extra,76,77,love ,79,extraextra,love ,82,83,love ,extraextra,86,love ,88,89,extra,91,92,love ,94,extraextra,love ,97,98,love ,extraextra,
My question:
How to delete only the very last comma?

Answer 1

Add a condition for the last value of num. The full code would be:
#include <iostream>
using namespace std;
void result(int test)
{
for (int num = 1; num <= test; num++)
{
if (num % 3 == 0 && num % 5 == 0)
cout << "extra";
else if (num % 3 == 0 )
cout << "love ";
else if(num %5 == 0)
cout << "extraextra";
else
cout << num;
if(num < test) cout << ","; // Here you add the condition
}
cout << endl; // Allows for flushing the output (Thanks #bruno)
}
int main()
{
int test = 100;
result(test);
return 0;
}

Answer 2

In case you really do not like the additional test of num visible in
for (int num = 1; num <= test; num++)
{
if (num % 3 == 0 && num % 5 == 0)
cout << "extra";
else if (num % 3 == 0 )
cout << "love ";
else if(num %5 == 0)
cout << "extraextra";
else
cout << num;
if (num < test)
cout << ',';
}
and
for (int num = 1; num <= test; num++)
{
if (num != 1)
cout << ',';
if (num % 3 == 0 && num % 5 == 0)
cout << "extra";
else if (num % 3 == 0 )
cout << "love ";
else if(num %5 == 0)
cout << "extraextra";
else
cout << num;
}
you can avoid that explicit test doing :
const char * sep = "";
for (int num = 1; num <= test; num++)
{
cout << sep;
sep = ",";
if (num % 3 == 0 && num % 5 == 0)
cout << "extra";
else if (num % 3 == 0 )
cout << "love ";
else if(num %5 == 0)
cout << "extraextra";
else
cout << num;
}
but probably this is less readable and a (very) little more expensive at the execution

Answer 3

Your loop runs for the last time at num == test, so just print commas for num less than test or num not equal to test.
i.e. simply replace cout << ","; with:
if(num < test) cout << ",";
or
if(num != test) cout << ",";

Answer 4

After having read all the suggestion and the constructive critics, I modified my answer in the following way:
#include <iostream>
using namespace std;
void singlecheck(int num){
if (num % 3 == 0 && num % 5 == 0)
cout << "extra";
else if (num % 3 == 0 )
cout << "love ";
else if(num %5 == 0)
cout << "extraextra";
else
cout << num;
}
void result(int test)
{
if(test>0){
for (int num = 1; num <test; num++){
singlecheck(num);
cout << ", ";
}
singlecheck(test);
cout << endl;
}
}
int main()
{
int test = 15;
result(test);
return 0;
}
I added one more function, which is doing the "test" job, while the cycle is done in another function. Now the result is correct also with input 0: I added one if at the beginning. In this way, only one if-check has to be done instead of a total of test if-checks, which was my principal concern. Previous version has repeated code which is not a good programming practice.