View Compilation Error

0_0_38550626_23627.cpp: In function 'int main()':
0_0_38550626_23627.cpp:7:25: error: unable to find numeric literal operator 'operator""Bpow'
     s=sqrt(pow(x2-x1,2)%2Bpow(y2-y1,2));
                         ^
0_0_38550626_23627.cpp:7:25: note: use -std=gnu++11 or -fext-numeric-literals to enable more built-in suffixes