View Compilation Error

0_0_24582117_16170.cpp: In function 'int main()':
0_0_24582117_16170.cpp:63:15: error: unable to find numeric literal operator 'operator""a'
     int cases=0a;
               ^
0_0_24582117_16170.cpp:63:15: note: use -std=gnu++11 or -fext-numeric-literals to enable more built-in suffixes