View Compilation Error

0_0_1483752_11185.cpp: In function `int main()':
0_0_1483752_11185.cpp:35: error: `qsort' undeclared (first use this function)
0_0_1483752_11185.cpp:35: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_1483752_11185.cpp:36: error: `memset' undeclared (first use this function)