foo.cpp: In function 'void init()':
foo.cpp:39:12: error: 'qsort' was not declared in this scope
 qsort(1,dxn);
            ^
foo.cpp:40:13: error: 'qsort2' was not declared in this scope
 qsort2(1,dyn);
             ^
foo.cpp:42:11: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
 if(dy[i]==dy&&i+1<=dyn)
           ^
foo.cpp: In function 'void work()':
foo.cpp:61:3: error: invalid conversion from 'long int*' to 'long long int' [-fpermissive]
 y1=dy;
   ^
foo.cpp:64:15: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
 if(dx[j].low<=dy && dx[j].high >= dy[i])
               ^
foo.cpp:55:6: warning: unused variable 'low' [-Wunused-variable]
 long low=0;
      ^