View Compilation Error

0_0_12356927_25370.cpp: In function `int main()':
0_0_12356927_25370.cpp:29: error: `sort' undeclared (first use this function)
0_0_12356927_25370.cpp:29: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_12356927_25370.cpp:54: error: overloaded function with no contextual type information