/in/foo.c: In function 'main':
/in/foo.c:8:26: warning: suggest parentheses around comparison in operand of '^' [-Wparentheses]
 if(m <= 0 || n <= 0 || m > 10^ 18 || n > 10^ 18) return 0;
                        ~~^~~~
/in/foo.c:8:40: warning: suggest parentheses around comparison in operand of '^' [-Wparentheses]
 if(m <= 0 || n <= 0 || m > 10^ 18 || n > 10^ 18) return 0;
                                      ~~^~~~