#pragma GCC optimize("Ofast") #pragma GCC target("avx2") #define rd_init() char*rp=({char*mmap();mmap(0l,1l<<25,1,2,0,0ll);}) #define rd() ({int _v=0,_c;while(_c=*rp++-48,_c>=0)_v=_v*10+_c;_v;}) #define wt(v) ({ulong _z=v;do*--wp=_z%10+48;while(_z/=10);}) #define wt1(v) ({char wbuf[64],*wp=wbuf+sizeof wbuf;wt(v);write(1,wp,wbuf+sizeof wbuf-wp);}) #define rep(v,e) for(typeof(e) v=0;v<e;++v) #define min(a,b) (a<=b?a:b) typedef unsigned long ulong; int z; int d[10]; int e[40]; void f(unsigned a,int b){ if(!b){ z+=!e[a%40]++; }else{ rep(i,10){ if(d[i]){ --d[i]; f(a*10+i,b-1); ++d[i]; } } } } int main(){ rd_init(); int n=rd(); rep(i,n){ d[*rp++&15]+=1; } f(0,min(n,3)); wt1(z); _exit(0); }