View Compilation Error

0_0_37948441_10731.cpp: In function 'int main()':
0_0_37948441_10731.cpp:16:16: error: 'judge' was not declared in this scope
    if(judge(mid)) r=mid;
                ^
0_0_37948441_10731.cpp:19:13: error: 'judge' was not declared in this scope
   if(judge(l)) cout << l << endl;
             ^