View Compilation Error

0_0_7581386_30364.cpp:5: error: ISO C++ forbids declaration of `a' with no type
0_0_7581386_30364.cpp:5: error: ISO C++ forbids declaration of `b' with no type
0_0_7581386_30364.cpp: In function `int main()':
0_0_7581386_30364.cpp:21: error: invalid conversion from `int (*)(const int*, const int*)' to `int (*)(const void*, const void*)'
0_0_7581386_30364.cpp:21: error:   initializing argument 4 of `void qsort(void*, size_t, size_t, int (*)(const void*, const void*))'