View Compilation Error

0_0_14101680_26031.cpp: In function 'double dis(P, P)':
0_0_14101680_26031.cpp:46:18: error: expected primary-expression at end of input
  return (a-b).len(
                  ^
0_0_14101680_26031.cpp:46:18: error: expected ';' at end of input
0_0_14101680_26031.cpp:46:18: error: expected '}' at end of input