/in/foo.cc:4:1: error: 'INF' does not name a type
 INF=0x7fffffff;
 ^~~
/in/foo.cc:5:1: error: 'MOD' does not name a type
 MOD=10000;
 ^~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:19:50: error: 'MOD' was not declared in this scope
                 if(f[i]==f[j]+1)p[i]=(p[i]+p[j])%MOD;
                                                  ^~~
/in/foo.cc:18:15: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
             if(a[j]>a[i])
               ^
/in/foo.cc:23:54: error: 'MOD' was not declared in this scope
     for(int i=1;i<=n;i++)if(f[i]==ans)tot=(tot+p[i])%MOD;
                                                      ^~~