View Compilation Error

0_0_32325314_24029.cpp: In function 'int main()':
0_0_32325314_24029.cpp:73:4: error: unable to find numeric literal operator 'operator""int'
    5int ans = bfs();
    ^
0_0_32325314_24029.cpp:73:4: note: use -std=gnu++11 or -fext-numeric-literals to enable more built-in suffixes
0_0_32325314_24029.cpp:74:7: error: 'ans' was not declared in this scope
   if (ans == inf)
       ^