int main(void) {

    char outer = 'c';

    for(int i=0; i<10; i++) {
        char inner = 'x';

        printf("%c", outer); // this works
        printf("%c", inner); // this also works
    }

    printf("%c", outer); // this works
    printf("%c", inner); // this doesn't work because inner is only valid between the { } in the for loop.
}