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