/in/foo.c: In function 'main':
/in/foo.c:16:5: warning: implicit declaration of function 'search' [-Wimplicit-function-declaration]
     search(beginx,beginy,begin,a,v,m,sum,max);
     ^~~~~~
/in/foo.c:6:8: warning: unused variable 'j' [-Wunused-variable]
  int i,j,a[1000][2],v[1000];
        ^
/in/foo.c: At top level:
/in/foo.c:20:6: warning: conflicting types for 'search'
 void search(int beginx,int beginy,int begin,int a[][2],int v[],int m,int sum,int max[])
      ^~~~~~
/in/foo.c:16:5: note: previous implicit declaration of 'search' was here
     search(beginx,beginy,begin,a,v,m,sum,max);
     ^~~~~~
/in/foo.c: In function 'search':
/in/foo.c:24:9: warning: implicit declaration of function 'xx' [-Wimplicit-function-declaration]
  int ff=xx(a,m,beginx+1,a[beginx][1-beginy]);
         ^~