long a,b,c;g(a,b){return b?g(b,a%b):a;}main(n){scanf("%d%d%d%d",&n,&a,&b,&c);a=!printf("%d",n/a+n/b+n/c-n*g(a,b)/a/b-n*g(c,b)/b/c-n/(a*=c/g(a,c))+n*g(a,b)/a/b);}