| Easy Puzzle #13 - One Possible Solution Approach | |||||||||||
| NB: There is only one final solution to this Sudoku puzzle | |||||||||||
| Rules: Place a number from 1-9 in each empty cell so that each row, each column AND each 3x3 block contains all the numbers from 1-9. | |||||||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | |||||||||||
| 2 | AA | BB | CC | Reference to 3x3 Blocks AA, BB & CC | |||||||
| 3 | |||||||||||
| 4 | |||||||||||
| 5 | DD | EE | FF | Reference to 3x3 Blocks DD, EE & FF | |||||||
| 6 | |||||||||||
| 7 | |||||||||||
| 8 | GG | HH | II | Reference to 3x3 Blocks GG, HH & II | |||||||
| 9 | |||||||||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 3 | 5 | 6 | Easy Puzzle #13 - October 13, 2005 | |||||||
| 2 | 5 | 6 | 2 | 8 | 3 | 4 | Original puzzle as published on joe-ks.com | ||||
| 3 | 2 | 3 | 7 | ||||||||
| 4 | 8 | 5 | |||||||||
| 5 | 9 | 4 | 3 | 2 | 8 | 1 | |||||
| 6 | 7 | 9 | 5 | ||||||||
| 7 | 7 | 4 | 8 | 1 | 9 | ||||||
| 8 | 6 | 8 | 4 | ||||||||
| 9 | 3 | 2 | 9 | 4 | 6 | 1 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 3 | 5 | 6 | 2 | Step 1: #2 is in Rows 2 & 3: #2 MUST go in Cell I1 | ||||||
| 2 | 5 | 6 | 2 | 8 | 3 | 4 | (cf #2 in Column G @ G5 excludes use of Cell G1) | ||||
| 3 | 2 | 3 | 7 | ||||||||
| 4 | 8 | 5 | Step 2: #6 is in Rows 8 & 9: #6 MUST go in Cell D7 | ||||||||
| 5 | 9 | 4 | 3 | 2 | 8 | 1 | |||||
| 6 | 7 | 9 | 5 | ||||||||
| 7 | 7 | 4 | 8 | 1 | 9 | ||||||
| 8 | 6 | 8 | 4 | ||||||||
| 9 | 3 | 2 | 9 | 4 | 6 | 1 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 7 | 3 | 5 | 6 | 2 | Step 3: #7 is in Columns A & B: #7 MUST go in Cell C1 | |||||
| 2 | 5 | 6 | 2 | 8 | 3 | 4 | (cf #7 in Row 3 @ Cell h3 excludes use of Cell C3) | ||||
| 3 | 2 | 3 | 7 | 8 | |||||||
| 4 | 8 | 5 | |||||||||
| 5 | 9 | 4 | 3 | 2 | 8 | 1 | Step 4: #8 is in Columns G & H: #8 MUST go in Cell I3 | ||||
| 6 | 7 | 9 | 5 | ||||||||
| 7 | 7 | 4 | 8 | 1 | 9 | ||||||
| 8 | 6 | 8 | 4 | ||||||||
| 9 | 3 | 2 | 9 | 4 | 6 | 1 | |||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 7 | 3 | 5 | 6 | 2 | Step 5: #5 is in Rows 1 & 2: #5 MUST go in Cell G3 | |||||
| 2 | 5 | 6 | 2 | 8 | 3 | 4 | |||||
| 3 | 2 | 3 | 5 | 7 | 8 | Step 6: #5 is in Rows 4 & 6: #5 MUST go in Cell C6 | |||||
| 4 | 8 | 5 | (cf #5 in Column B @ B2 excludes use of Cell B6) | ||||||||
| 5 | 9 | 5 | 4 | 3 | 2 | 8 | 1 | ||||
| 6 | 7 | 9 | 5 | Step 7: #8 is in Rows 7 & 8: #8 MUST go in Cell C9 | |||||||
| 7 | 7 | 4 | 8 | 1 | 9 | ||||||
| 8 | 6 | 8 | 4 | ||||||||
| 9 | 3 | 2 | 8 | 9 | 4 | 6 | 1 | ||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 8 | 7 | 3 | 5 | 1 | 6 | 2 | Step 8: #8 is in Columns B & C: #8 MUST go in Cell A1 | |||
| 2 | 5 | 6 | 2 | 8 | 3 | 4 | (cf #8 in Row 2 @ F2 excludes use of Cell A2) | ||||
| 3 | 2 | 3 | 5 | 7 | 8 | ||||||
| 4 | 8 | 5 | |||||||||
| 5 | 9 | 5 | 4 | 3 | 2 | 8 | 1 | Step 9: #1 is in Columns H & I: #9 MUST go in Cell G1 | |||
| 6 | 7 | 9 | 5 | ||||||||
| 7 | 7 | 4 | 8 | 1 | 9 | ||||||
| 8 | 6 | 8 | 4 | ||||||||
| 9 | 3 | 2 | 8 | 9 | 4 | 6 | 1 | ||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 8 | 4 | 7 | 3 | 5 | 1 | 6 | 2 | Step 10: Complete Block CC: #9 MUST go in Cell H2 | ||
| 2 | 5 | 6 | 2 | 8 | 3 | 9 | 4 | ||||
| 3 | 2 | 3 | 5 | 7 | 8 | Step 11: #8 is in Columns E & F: #8 MUST go in Cell D6 | |||||
| 4 | 8 | 5 | |||||||||
| 5 | 9 | 5 | 4 | 3 | 2 | 8 | 1 | Step 12: Block AA needs #4: #4 MUST go in Cell B1 | |||
| 6 | 7 | 8 | 9 | 5 | (#4 in Row 2 @ I2 excludes Cell A2, & #4 in Column C @ | ||||||
| 7 | 7 | 4 | 8 | 1 | 9 | C7 excludes Cell C3) | |||||
| 8 | 6 | 8 | 4 | ||||||||
| 9 | 3 | 2 | 8 | 9 | 4 | 6 | 1 | ||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 8 | 4 | 7 | 3 | 5 | 9 | 1 | 6 | 2 | Step 13: Complete Column B: #1 MUST go in Cell B6 | |
| 2 | 5 | 6 | 2 | 8 | 3 | 9 | 4 | ||||
| 3 | 2 | 3 | 5 | 7 | 8 | Step 14: Complete Row 1: #9 MUST go in Cell F1 | |||||
| 4 | 8 | 5 | |||||||||
| 5 | 9 | 5 | 4 | 3 | 2 | 8 | 1 | ||||
| 6 | 7 | 1 | 8 | 9 | 5 | ||||||
| 7 | 7 | 4 | 8 | 1 | 9 | ||||||
| 8 | 6 | 8 | 4 | ||||||||
| 9 | 3 | 2 | 8 | 9 | 4 | 6 | 1 | ||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 8 | 4 | 7 | 3 | 5 | 9 | 1 | 6 | 2 | Step 15: #7 is in Rows 1 & 3: #7 MUST go in Cell E2 | |
| 2 | 5 | 6 | 2 | 7 | 8 | 3 | 9 | 4 | |||
| 3 | 2 | 3 | 5 | 7 | 8 | ||||||
| 4 | 8 | 5 | 1 | Step 16: Block EE needs #1: #1 MUST go in Cell E4 | |||||||
| 5 | 9 | 5 | 4 | 3 | 2 | 8 | 1 | (#1 in Column F @ F7 excludes use of F4, F5 & F6) | |||
| 6 | 7 | 1 | 8 | 9 | 5 | ||||||
| 7 | 7 | 4 | 8 | 1 | 9 | 2 | Step 17: Block II needs #2: #2 MUST go in Cell H7 | ||||
| 8 | 6 | 8 | 4 | (#2 in Column I @ I1 excludes use of I7, I8 & I9) | |||||||
| 9 | 3 | 2 | 8 | 9 | 4 | 6 | 1 | ||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 8 | 4 | 7 | 3 | 5 | 9 | 1 | 6 | 2 | Step 18: Complete Row 2: #1 MUST go in Cell A2 | |
| 2 | 1 | 5 | 6 | 2 | 7 | 8 | 3 | 9 | 4 | ||
| 3 | 2 | 3 | 5 | 7 | 8 | Step 19: #9 is in Rows 5 & 6: #9 MUST go in Cell I4 | |||||
| 4 | 8 | 5 | 1 | 9 | (#9 in Column G @ G7 excludes G4, & #9 in Column H @ | ||||||
| 5 | 9 | 5 | 4 | 3 | 2 | 8 | 1 | H2 excludes H4) | |||
| 6 | 7 | 1 | 8 | 9 | 5 | ||||||
| 7 | 7 | 4 | 8 | 1 | 9 | 2 | |||||
| 8 | 6 | 8 | 4 | ||||||||
| 9 | 3 | 2 | 8 | 9 | 4 | 6 | 1 | ||||
| A | B | C | D | E | F | G | H | I | |||
| 1 | 8 | 4 | 7 | 3 | 5 | 9 | 1 | 6 | 2 | Step 20: Complete Block AA: #9 MUST go in Cell C3 | |
| 2 | 1 | 5 | 6 | 2 | 7 | 8 | 3 | 9 | 4 | ||
| 3 | 2 | 3 | 9 | 5 | 7 | 8 | Step 21: Complete Column H: #3 MUST go in Cell H4 | ||||
| 4 | 8 | ||||||||||