int t[131068];int f=0;int l=0;void m(int*t,int i){int g;int z=l;int c=0;while(z<=f){g=t[z]*i+c;t[z]=g%10;c=g/10;z=z+1;}if(c!=0){f=f+1;t[f]=c;}}main(int a,char**r){int n,i,k;t[l]=1;n=atoi(r[1]);for(i=1;i<=n;i++)m(t,i);for(i=f;i>=l;--i)printf("%u",t[i]);printf("\n");}