syntax - How to set similar constraints on multiple variables in Solve

In this equation:

var = {x, y, z, m};
Solve[x + 2y + z + m == 14 && And @@ Thread[2 <= var <= 3], var, Integers]

{{x->2,y->3,z->3,m->3},{x->3,y->3,z->2,m->3},{x->3,y->3,z->3,m->2}}

But I think ...And @@ Thread[2 <= var <= 3]...Integers is very ugly. So I give this another try as follows:

var = {x, y, z, m};

Solve[x + 2y + z + m == 14 && (Alternatives@@ var == (2|3)), var]

But I get some error information.

I would like to know whether there are better methods to do do this.

Answer

In version 10, you can use this simpler syntax without Thread:

Solve[x+2y+z+m==14&&2<=var<=3,var,Integers]

{{x->2,y->3,z->3,m->3},{x->3,y->3,z->2,m->3},{x->3,y->3,z->3,m->2}}

Comments

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