View Compilation Error

0_0_28986525_18958.cpp: In function 'long long int pollard_rho(long long int, long long int)':
0_0_28986525_18958.cpp:72:15: error: expected primary-expression at end of input
             k <<
               ^
0_0_28986525_18958.cpp:72:15: error: expected '}' at end of input
0_0_28986525_18958.cpp:72:15: error: expected '}' at end of input
0_0_28986525_18958.cpp:72:15: error: expected '}' at end of input