Language: C

x=1000,a=100000,i;main(n){scanf("%d",&n);for(;i++<n;a/=x,a*=x){a*=1.05;a%x&&a+=x;}printf("%d\n",a);exit(0);}

Compiler output:
main.c:1:1: warning: data definition has no type or storage class
    1 | x=1000,a=100000,i;main(n){scanf("%d",&n);for(;i++<n;a/=x,a*=x){a*=1.05;a%x&&a+=x;}printf("%d\n",a);exit(0);}
      | ^
main.c:1:1: error: type defaults to 'int' in declaration of 'x' [-Wimplicit-int]
main.c:1:8: error: type defaults to 'int' in declaration of 'a' [-Wimplicit-int]
    1 | x=1000,a=100000,i;main(n){scanf("%d",&n);for(;i++<n;a/=x,a*=x){a*=1.05;a%x&&a+=x;}printf("%d\n",a);exit(0);}
      |        ^
main.c:1:17: error: type defaults to 'int' in declaration of 'i' [-Wimplicit-int]
    1 | x=1000,a=100000,i;main(n){scanf("%d",&n);for(;i++<n;a/=x,a*=x){a*=1.05;a%x&&a+=x;}printf("%d\n",a);exit(0);}
      |                 ^
main.c:1:19: error: return type defaults to 'int' [-Wimplicit-int]
    1 | x=1000,a=100000,i;main(n){scanf("%d",&n);for(;i++<n;a/=x,a*=x){a*=1.05;a%x&&a+=x;}printf("%d\n",a);exit(0);}
      |                   ^~~~
main.c: In function 'main':
main.c:1:19: error: type of 'n' defaults to 'int' [-Wimplicit-int]
main.c:1:27: error: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
    1 | x=1000,a=100000,i;main(n){scanf("%d",&n);for(;i++<n;a/=x,a*=x){a*=1.05;a%x&&a+=x;}printf("%d\n",a);exit(0);}
      |                           ^~~~~
main.c:1:1: note: include '<stdio.h>' or provide a declaration of 'scanf'
  +++ |+#include <stdio.h>
    1 | x=1000,a=100000,i;main(n){scanf("%d",&n);for(;i++<n;a/=x,a*=x){a*=1.05;a%x&&a+=x;}printf("%d\n",a);exit(0);}
main.c:1:27: warning: incompatible implicit declaration of built-in function 'scanf' [-Wbuiltin-declaration-mismatch]
    1 | x=1000,a=100000,i;main(n){scanf("%d",&n);for(;i++<n;a/=x,a*=x){a*=1.05;a%x&&a+=x;}printf("%d\n",a);exit(0);}
      |                           ^~~~~
main.c:1:27: note: include '<stdio.h>' or provide a declaration of 'scanf'
main.c:1:78: error: lvalue required as left operand of assignment
    1 | x=1000,a=100000,i;main(n){scanf("%d",&n);for(;i++<n;a/=x,a*=x){a*=1.05;a%x&&a+=x;}printf("%d\n",a);exit(0);}
      |                                                                              ^~
main.c:1:83: error: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
    1 | x=1000,a=100000,i;main(n){scanf("%d",&n);for(;i++<n;a/=x,a*=x){a*=1.05;a%x&&a+=x;}printf("%d\n",a);exit(0);}
      |                                                                                   ^~~~~~
main.c:1:83: note: include '<stdio.h>' or provide a declaration of 'printf'
main.c:1:83: warning: incompatible implicit declaration of built-in function 'printf' [-Wbuiltin-declaration-mismatch]
main.c:1:83: note: include '<stdio.h>' or provide a declaration of 'printf'
main.c:1:100: error: implicit declaration of function 'exit' [-Wimplicit-function-declaration]
    1 | x=1000,a=100000,i;main(n){scanf("%d",&n);for(;i++<n;a/=x,a*=x){a*=1.05;a%x&&a+=x;}printf("%d\n",a);exit(0);}
      |                                                                                                    ^~~~
main.c:1:1: note: include '<stdlib.h>' or provide a declaration of 'exit'
  +++ |+#include <stdlib.h>
    1 | x=1000,a=100000,i;main(n){scanf("%d",&n);for(;i++<n;a/=x,a*=x){a*=1.05;a%x&&a+=x;}printf("%d\n",a);exit(0);}
main.c:1:100: warning: incompatible implicit declaration of built-in function 'exit' [-Wbuiltin-declaration-mismatch]
    1 | x=1000,a=100000,i;main(n){scanf("%d",&n);for(;i++<n;a/=x,a*=x){a*=1.05;a%x&&a+=x;}printf("%d\n",a);exit(0);}
      |                                                                                                    ^~~~
main.c:1:100: note: include '<stdlib.h>' or provide a declaration of 'exit'