# another example by Haghighat and Polychronopoulos
# 1 <= i <= 2n
# 1 <= j <= i
# 1 <= j <= 2n-i
#---------------
5 5
1 1 0 0 -1
1 -1 0 2 0
1 0 1 0 -1
1 1 -1 0 0
1 -1 -1 2 0

1 3
1 1 -1

n
Haghighat and Polychronopoulos example
