/in/foo.c: In function 'main':
/in/foo.c:21:11: warning: too many arguments for format [-Wformat-extra-args]
    printf("lld",-1);
           ^~~~~
/in/foo.c:3:20: warning: unused variable 'j' [-Wunused-variable]
  long long n,a,b,i,j,ans,
                    ^