#include <stdio>

int main() {
    char a[12];

    int b = scanf("%11s", a);

    if (b != 1) { return 0; };

    if (printf("%s", a) != 11) {
       
        return 0;
    };

    return 0;
}

1 – are scanf and printf here used safely ?

2 – am i missing some checks ? i wanna make 100% bug free code in c

3 – is the only issue in scanf buffer overflow ? is it fixed in the above code ?

the purpose of all this is to make a c 100% safe code