/in/foo.c: In function 'main':
/in/foo.c:6:10: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'float *' [-Wformat=]
  scanf("%d %d %d %d",&x1,&x2,&y1,&y2);
          ^
/in/foo.c:6:13: warning: format '%d' expects argument of type 'int *', but argument 3 has type 'float *' [-Wformat=]
  scanf("%d %d %d %d",&x1,&x2,&y1,&y2);
             ^
/in/foo.c:6:16: warning: format '%d' expects argument of type 'int *', but argument 4 has type 'float *' [-Wformat=]
  scanf("%d %d %d %d",&x1,&x2,&y1,&y2);
                ^
/in/foo.c:6:19: warning: format '%d' expects argument of type 'int *', but argument 5 has type 'float *' [-Wformat=]
  scanf("%d %d %d %d",&x1,&x2,&y1,&y2);
                   ^