CASE 1: NEVER
CASE 2: 2
CASE 3: NEVER
CASE 4: 1
CASE 5: NEVER
CASE 6: 1
CASE 7: NEVER
CASE 8: 2
CASE 9: 1
CASE 10: 2
CASE 11: 1
CASE 12: 2
CASE 13: 1
CASE 14: 3
CASE 15: 1
CASE 16: 7
CASE 17: 4
CASE 18: 3
CASE 19: 2
CASE 20: 1
CASE 21: NEVER
CASE 22: NEVER
CASE 23: 6
CASE 24: 1
CASE 25: 2
CASE 26: NEVER
CASE 27: 1
CASE 28: NEVER
CASE 29: 4
CASE 30: NEVER
CASE 31: 2