View Compilation Error

0_0_14585427_23377.cpp: In function 'int main()':
0_0_14585427_23377.cpp:25:15: error: unable to find numeric literal operator 'operator""i'
      if (k == 1i || s[i - 1] == t[i]) {
               ^
0_0_14585427_23377.cpp:25:15: note: use -std=gnu++11 or -fext-numeric-literals to enable more built-in suffixes