Language: C

u[9];D(s,v){int i,r;if(!s)return!v;if(v<0||v>s*-~s*5)return 0;for(r=i=0;i<=9;++i)!u[i]?u[i]=1,r+=D(s-1,v-i*s),u[i]=0;return r;}main(n,v){while(~scanf("%d%d",&n,&v))printf("%d\n",D(n,v));exit(0);}

Compiler output:
main.c:1:1: warning: data definition has no type or storage class
    1 | u[9];D(s,v){int i,r;if(!s)return!v;if(v<0||v>s*-~s*5)return 0;for(r=i=0;i<=9;++i)!u[i]?u[i]=1,r+=D(s-1,v-i*s),u[i]=0;return r;}main(n,v){while(~scanf("%d%d",&n,&v))printf("%d\n",D(n,v));exit(0);}
      | ^
main.c:1:1: error: type defaults to 'int' in declaration of 'u' [-Wimplicit-int]
main.c:1:6: error: return type defaults to 'int' [-Wimplicit-int]
    1 | u[9];D(s,v){int i,r;if(!s)return!v;if(v<0||v>s*-~s*5)return 0;for(r=i=0;i<=9;++i)!u[i]?u[i]=1,r+=D(s-1,v-i*s),u[i]=0;return r;}main(n,v){while(~scanf("%d%d",&n,&v))printf("%d\n",D(n,v));exit(0);}
      |      ^
main.c: In function 'D':
main.c:1:6: error: type of 's' defaults to 'int' [-Wimplicit-int]
main.c:1:6: error: type of 'v' defaults to 'int' [-Wimplicit-int]
main.c:1:117: error: expected ':' before ';' token
    1 | u[9];D(s,v){int i,r;if(!s)return!v;if(v<0||v>s*-~s*5)return 0;for(r=i=0;i<=9;++i)!u[i]?u[i]=1,r+=D(s-1,v-i*s),u[i]=0;return r;}main(n,v){while(~scanf("%d%d",&n,&v))printf("%d\n",D(n,v));exit(0);}
      |                                                                                                                     ^
      |                                                                                                                     :
main.c: At top level:
main.c:1:128: error: return type defaults to 'int' [-Wimplicit-int]
    1 | u[9];D(s,v){int i,r;if(!s)return!v;if(v<0||v>s*-~s*5)return 0;for(r=i=0;i<=9;++i)!u[i]?u[i]=1,r+=D(s-1,v-i*s),u[i]=0;return r;}main(n,v){while(~scanf("%d%d",&n,&v))printf("%d\n",D(n,v));exit(0);}
      |                                                                                                                                ^~~~
main.c: In function 'main':
main.c:1:128: error: type of 'n' defaults to 'int' [-Wimplicit-int]
main.c:1:128: error: type of 'v' defaults to 'int' [-Wimplicit-int]
main.c:1:145: error: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
    1 | u[9];D(s,v){int i,r;if(!s)return!v;if(v<0||v>s*-~s*5)return 0;for(r=i=0;i<=9;++i)!u[i]?u[i]=1,r+=D(s-1,v-i*s),u[i]=0;return r;}main(n,v){while(~scanf("%d%d",&n,&v))printf("%d\n",D(n,v));exit(0);}
      |                                                                                                                                                 ^~~~~
main.c:1:1: note: include '<stdio.h>' or provide a declaration of 'scanf'
  +++ |+#include <stdio.h>
    1 | u[9];D(s,v){int i,r;if(!s)return!v;if(v<0||v>s*-~s*5)return 0;for(r=i=0;i<=9;++i)!u[i]?u[i]=1,r+=D(s-1,v-i*s),u[i]=0;return r;}main(n,v){while(~scanf("%d%d",&n,&v))printf("%d\n",D(n,v));exit(0);}
main.c:1:145: warning: incompatible implicit declaration of built-in function 'scanf' [-Wbuiltin-declaration-mismatch]
    1 | u[9];D(s,v){int i,r;if(!s)return!v;if(v<0||v>s*-~s*5)return 0;for(r=i=0;i<=9;++i)!u[i]?u[i]=1,r+=D(s-1,v-i*s),u[i]=0;return r;}main(n,v){while(~scanf("%d%d",&n,&v))printf("%d\n",D(n,v));exit(0);}
      |                                                                                                                                                 ^~~~~
main.c:1:145: note: include '<stdio.h>' or provide a declaration of 'scanf'
main.c:1:165: error: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
    1 | u[9];D(s,v){int i,r;if(!s)return!v;if(v<0||v>s*-~s*5)return 0;for(r=i=0;i<=9;++i)!u[i]?u[i]=1,r+=D(s-1,v-i*s),u[i]=0;return r;}main(n,v){while(~scanf("%d%d",&n,&v))printf("%d\n",D(n,v));exit(0);}
      |                                                                                                                                                                     ^~~~~~
main.c:1:165: note: include '<stdio.h>' or provide a declaration of 'printf'
main.c:1:165: warning: incompatible implicit declaration of built-in function 'printf' [-Wbuiltin-declaration-mismatch]
main.c:1:165: note: include '<stdio.h>' or provide a declaration of 'printf'
main.c:1:187: error: implicit declaration of function 'exit' [-Wimplicit-function-declaration]
    1 | u[9];D(s,v){int i,r;if(!s)return!v;if(v<0||v>s*-~s*5)return 0;for(r=i=0;i<=9;++i)!u[i]?u[i]=1,r+=D(s-1,v-i*s),u[i]=0;return r;}main(n,v){while(~scanf("%d%d",&n,&v))printf("%d\n",D(n,v));exit(0);}
      |                                                                                                                                                                                           ^~~~
main.c:1:1: note: include '<stdlib.h>' or provide a declaration of 'exit'
  +++ |+#include <stdlib.h>
    1 | u[9];D(s,v){int i,r;if(!s)return!v;if(v<0||v>s*-~s*5)return 0;for(r=i=0;i<=9;++i)!u[i]?u[i]=1,r+=D(s-1,v-i*s),u[i]=0;return r;}main(n,v){while(~scanf("%d%d",&n,&v))printf("%d\n",D(n,v));exit(0);}
main.c:1:187: warning: incompatible implicit declaration of built-in function 'exit' [-Wbuiltin-declaration-mismatch]
    1 | u[9];D(s,v){int i,r;if(!s)return!v;if(v<0||v>s*-~s*5)return 0;for(r=i=0;i<=9;++i)!u[i]?u[i]=1,r+=D(s-1,v-i*s),u[i]=0;return r;}main(n,v){while(~scanf("%d%d",&n,&v))printf("%d\n",D(n,v));exit(0);}
      |                                                                                                                                                                                           ^~~~
main.c:1:187: note: include '<stdlib.h>' or provide a declaration of 'exit'