Dear all, I appreciate to let me know if there is any method in R to find all the possible solutions (non-negative integers) to the following constraint partitioning problem: X_1+X_2+...+X_(2k)=N X_1+X_2<=r_1 X_3+X_4<=r_2 X_5+X_6<=r_3 ..... X(2k-1)+X(2k)=r_k Thank you, Amin Zollanvari