Test Cases failed

#1

#include
using namespace std;

int main(){
int f = 0;
int c;

	while(f<=100){
	c = (5*(f-32)/9);
	cout <<f<<"\t"<<c<<endl;
	f = f + 20;
	}
return 0;

}

I’m new to coding, I tried this code but it’s getting test cases failed even though it executed and and getting result on IDE and I have tried with the constraint also. Please clear it up, and explain how I have approach here, Sir. Thanks you

#2

This is because you are not taking inputs!
you should take inputs from user
do it this way:
int start,end,step_size;
cin>>start>>end>>step_size;
f=start;
while(f<=start){
… do your work
f=f+step_size;
}