run->answer = 'f';
printf("%s\n",run->answer);
In the Flag struct, answer is a char but you're trying to print it as
a string. Try %c instead of %s.
run->answer = 'f';
printf("%s\n",run->answer);
In the Flag struct, answer is a char but you're trying to print it as
a string. Try %c instead of %s.