Language: C

#include<stdlib.h>
p(int*a,int*b){return*a-*b;}c,V,i,f[999];
main(d){for(;f[1]=scanf("%d%d",&V,&d)+1;printf("%d\n",c)){
for(f[0]=i=2;i<V;i++)f[i]=(f[i-1]+f[i-2])%1001;
qsort(f,V,4,p);
for(i=c=1;i<V;f[i]-f[i++-1]<d?:c++);}
div(0);}

Compiler output:
main.c:2:1: error: return type defaults to 'int' [-Wimplicit-int]
    2 | p(int*a,int*b){return*a-*b;}c,V,i,f[999];
      | ^
main.c:2:29: warning: data definition has no type or storage class
    2 | p(int*a,int*b){return*a-*b;}c,V,i,f[999];
      |                             ^
main.c:2:29: error: type defaults to 'int' in declaration of 'c' [-Wimplicit-int]
main.c:2:31: error: type defaults to 'int' in declaration of 'V' [-Wimplicit-int]
    2 | p(int*a,int*b){return*a-*b;}c,V,i,f[999];
      |                               ^
main.c:2:33: error: type defaults to 'int' in declaration of 'i' [-Wimplicit-int]
    2 | p(int*a,int*b){return*a-*b;}c,V,i,f[999];
      |                                 ^
main.c:2:35: error: type defaults to 'int' in declaration of 'f' [-Wimplicit-int]
    2 | p(int*a,int*b){return*a-*b;}c,V,i,f[999];
      |                                   ^
main.c:3:1: error: return type defaults to 'int' [-Wimplicit-int]
    3 | main(d){for(;f[1]=scanf("%d%d",&V,&d)+1;printf("%d\n",c)){
      | ^~~~
main.c: In function 'main':
main.c:3:1: error: type of 'd' defaults to 'int' [-Wimplicit-int]
main.c:3:19: error: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
    3 | main(d){for(;f[1]=scanf("%d%d",&V,&d)+1;printf("%d\n",c)){
      |                   ^~~~~
main.c:2:1: note: include '<stdio.h>' or provide a declaration of 'scanf'
    1 | #include<stdlib.h>
  +++ |+#include <stdio.h>
    2 | p(int*a,int*b){return*a-*b;}c,V,i,f[999];
main.c:3:19: warning: incompatible implicit declaration of built-in function 'scanf' [-Wbuiltin-declaration-mismatch]
    3 | main(d){for(;f[1]=scanf("%d%d",&V,&d)+1;printf("%d\n",c)){
      |                   ^~~~~
main.c:3:19: note: include '<stdio.h>' or provide a declaration of 'scanf'
main.c:3:41: error: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
    3 | main(d){for(;f[1]=scanf("%d%d",&V,&d)+1;printf("%d\n",c)){
      |                                         ^~~~~~
main.c:3:41: note: include '<stdio.h>' or provide a declaration of 'printf'
main.c:3:41: warning: incompatible implicit declaration of built-in function 'printf' [-Wbuiltin-declaration-mismatch]
main.c:3:41: note: include '<stdio.h>' or provide a declaration of 'printf'
main.c:5:13: error: passing argument 4 of 'qsort' from incompatible pointer type [-Wincompatible-pointer-types]
    5 | qsort(f,V,4,p);
      |             ^
      |             |
      |             int (*)(int *, int *)
In file included from main.c:1:
/usr/include/stdlib.h:971:34: note: expected '__compar_fn_t' {aka 'int (*)(const void *, const void *)'} but argument is of type 'int (*)(int *, int *)'
  971 |                    __compar_fn_t __compar) __nonnull ((1, 4));
      |                    ~~~~~~~~~~~~~~^~~~~~~~
main.c:7:1: error: too few arguments to function 'div'
    7 | div(0);}
      | ^~~
/usr/include/stdlib.h:992:14: note: declared here
  992 | extern div_t div (int __numer, int __denom)
      |              ^~~