/in/foo.c:3:6: warning: return type of 'main' is not 'int' [-Wmain]
 void main()
      ^~~~
/in/foo.c: In function 'main':
/in/foo.c:8:11: warning: format '%ld' expects argument of type 'long int *', but argument 2 has type 'int *' [-Wformat=]
  scanf("%ld%ld",&x1,&y1);
           ^
/in/foo.c:8:14: warning: format '%ld' expects argument of type 'long int *', but argument 3 has type 'int *' [-Wformat=]
  scanf("%ld%ld",&x1,&y1);
              ^
/in/foo.c:9:11: warning: format '%ld' expects argument of type 'long int *', but argument 2 has type 'int *' [-Wformat=]
  scanf("%ld%ld",&x2,&y2);
           ^
/in/foo.c:9:14: warning: format '%ld' expects argument of type 'long int *', but argument 3 has type 'int *' [-Wformat=]
  scanf("%ld%ld",&x2,&y2);
              ^
/in/foo.c:7:8: warning: unused variable 'count' [-Wunused-variable]
  int s,count;
        ^~~~~
/in/foo.c:6:11: warning: unused variable 'y3' [-Wunused-variable]
  float x3,y3;
           ^~
/in/foo.c:6:8: warning: unused variable 'x3' [-Wunused-variable]
  float x3,y3;
        ^~