param N := 2;

var x{1..N};

minimize f:
-x[1]*x[2];

subject to cons1:
x[1]^2 + x[2]^2 >= 0;

subject to cons2:
1 - x[1]^2 - x[2]^2 >= 0;

subject to cons3:
x[1] >= 0;

subject to cons4:
x[2] >= 0;

data;
var x:=
1	0.8
2	0.05;

solve;

display x;