View Compilation Error

0_0_20182989_419.cpp: In function 'int main()':
0_0_20182989_419.cpp:11:25: error: 'step' was not declared in this scope
   printf("%10d%10d    ",step,mod);
                         ^
0_0_20182989_419.cpp:11:30: error: 'mod' was not declared in this scope
   printf("%10d%10d    ",step,mod);
                              ^