param N := 4;

var x{1..N};

minimize f:
(x[1]+10*x[2])^2+5*(x[3]-x[4])^2+(x[2]-2*x[3])^4+10*(x[1]-x[4])^4;

data;
var x:=
1	3
2	-1
3	0
4	1;
solve;

display x;