MODEL:

[Z] Max = 500*(d_1 + d_2 + d_3 + d_4) - (0*(z_11 + z_21 + z_31 + z_41) + 16000*(z_12 + z_22 + z_32 + z_42) + 20500*(z_13 + z_23 + z_33 + z_43) + 25500*(z_14 + z_24 + z_34 + z_44) + 20*(i_1 + i_2 + i_3 + i_4));

d_1 = 40;
d_2 = 60;
d_3 = 75;
d_4 = 25;

x_1 <= 60;
x_2 <= 60;
x_3 <= 60;
x_4 <= 60;

i_1 = 10 + x_1 - d_1;
i_2 = i_1 + x_2 - d_2;
i_3 = i_2 + x_3 - d_3;
i_4 = i_3 + x_4 - d_4;

x_1 = 0*z_11 + 40*z_12 + 50*z_13 + 60*z_14;
x_2 = 0*z_21 + 40*z_22 + 50*z_23 + 60*z_24;
x_3 = 0*z_31 + 40*z_32 + 50*z_33 + 60*z_34;
x_4 = 0*z_41 + 40*z_42 + 50*z_43 + 60*z_44;

z_11 <= y_11;
z_12 <= y_11 + y_12;
z_13 <= y_12 + y_13;
z_14 <= y_13;

z_21 <= y_21;
z_22 <= y_21 + y_22;
z_23 <= y_22 + y_23;
z_24 <= y_23;

z_31 <= y_31;
z_32 <= y_31 + y_32;
z_33 <= y_32 + y_33;
z_34 <= y_33;

z_41 <= y_41;
z_42 <= y_41 + y_42;
z_43 <= y_42 + y_43;
z_44 <= y_43;

y_11 + y_12 + y_13 = 1;
y_21 + y_22 + y_23 = 1;
y_31 + y_32 + y_33 = 1;
y_41 + y_42 + y_43 = 1;

z_11 + z_12 + z_13 + z_14 = 1;
z_21 + z_22 + z_23 + z_24 = 1;
z_31 + z_32 + z_33 + z_34 = 1;
z_41 + z_42 + z_43 + z_44 = 1;

@BIN(y_11);
@BIN(y_12);
@BIN(y_13);

@BIN(y_21);
@BIN(y_22);
@BIN(y_23);

@BIN(y_31);
@BIN(y_32);
@BIN(y_33);

@BIN(y_41);
@BIN(y_42);
@BIN(y_43);

@GIN(x_1);
@GIN(x_2);
@GIN(x_3);
@GIN(x_4);

END