What is the output of the following code?

#include stdio.h
int main() {
    char c;
    printf("Enter a character: ");
    scanf("%c", &c);

    if ((c = 'a' && c = 'z') || (c = 'A' && c = 'Z'))
        printf("%c is an alphabet.", c);
    else
        printf("%c is not an alphabet.", c);

    return 0;
}

Enter a character :*