View Compilation Error

0_0_38031640_12925.cpp: In function 'int compare(const void*, const void*)':
0_0_38031640_12925.cpp:8:15: error: invalid conversion from 'const void*' to 'int*' [-fpermissive]
     int* p1 = e1;
               ^
0_0_38031640_12925.cpp:9:15: error: invalid conversion from 'const void*' to 'int*' [-fpermissive]
     int* p2 = e2;
               ^