Question { Infosys, 42860 }

how to print
1 2 3 4 5 6 7 8 9 10 9 8 7 6 5 4 3 2 1
using any loop(for or while) only once(only 1 loop) and
maximum 2 variables using C.

Answer

int i = 1,j=1;
do
{
printf("%d",i);
if (j<10)
i++;
else
i--;
j++;
}while(j<20);