1000 A+B Problem (0)
1004 Financial Management (0)
1003 Hangover (1)
1007 DNA Sorting (2)
2136 Vertical Histogram (2)
2140 Herd Sums (3)
1504 Adding Reversed Numbers (3)
1806 Manhattan 2025 (4)
1001 Exponentiation (5)
1922 Ride to School (5)
3251 Big Square (6, challenge problem)
1403 Hotline (9, challenge problem)