View Compilation Error

0_0_29720466_549.cpp: In function 'int main()':
0_0_29720466_549.cpp:24:14: error: unable to find numeric literal operator 'operator""x3f'
   memset(dis,0x3fx3f,sizeof(dis));
              ^
0_0_29720466_549.cpp:24:14: note: use -std=gnu++11 or -fext-numeric-literals to enable more built-in suffixes