View Compilation Error

0_0_38340720_17740.cpp: In function 'int main()':
0_0_38340720_17740.cpp:34:21: error: unable to find numeric literal operator 'operator""i'
         for(int i=n-1i>=0; i--)
                     ^
0_0_38340720_17740.cpp:34:21: note: use -std=gnu++11 or -fext-numeric-literals to enable more built-in suffixes
0_0_38340720_17740.cpp:34:31: error: expected ';' before ')' token
         for(int i=n-1i>=0; i--)
                               ^