View Compilation Error

0_0_12835921_16276.cpp:7: error: `acos' was not declared in this scope
0_0_12835921_16276.cpp: In function `double dist(point, point)':
0_0_12835921_16276.cpp:26: error: expected unqualified-id at end of input
0_0_12835921_16276.cpp:26: error: expected `,' or `;' at end of input
0_0_12835921_16276.cpp:26: error: expected `}' at end of input