Vietnam Snake
May 26, 2015
Today’s task is to solve a current exercise in recreational mathematics.
The Guardian recently published a math puzzle that is apparently given to third-grade students (eight-year old children) in Vietnam. The puzzle is a graphic in the form of a snake, and the digits 1 through 9 are to be inserted in the nine empty boxes in such a way as to make the formula correct. Although it may not be clear, the colon symbol is used for division, and the normal order of operations is to be preserved, so the formula becomes A + ((13 * B) / C) + D + (12 * E) − F − 11 + ((G * H) / I) − 10 = 66.
Your task is to write a program that generates all possible solutions to the problem. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.
Programming Praxis 