View Compilation Error

0_0_35897483_6686.cpp: In function 'long long int mul(long long int, long long int, long long int)':
0_0_35897483_6686.cpp:8:47: error: 'int_128' was not declared in this scope
  if((long long) ((long double)a/P*b+1e-6)*P!=(int_128)a*b/p*p)
                                               ^
0_0_35897483_6686.cpp:8:55: error: expected ')' before 'a'
  if((long long) ((long double)a/P*b+1e-6)*P!=(int_128)a*b/p*p)
                                                       ^