Solution to [Viral] Math Puzzle for Vietnamese Eight-Year-Olds (Using R)

baoloc.R

## The problem could be written as u + 13v/w + x + 12y - z - 11 + pq/r -10 = 66
## which reduces to u + 13v/w + x + 12y - z + pq/r = 87
## This problem was solved on [1] "Wed May 27 17:46:52 2015"

baoloc <- function()
{
  packages <- rownames(installed.packages())
  if("combinat" %in% packages) library("combinat") else install.packages("combinat")
  numbers <- 1:9
  permutations <- permn(numbers) ## list of all permutations of vector input
  solutions <- numeric(9)
  for(i in 1:length(permutations))
  {
    solution <- permutations[[i]]
    if(solution[1] + 13*(solution[2]/solution[3]) + solution[4] + 12*solution[5] - solution[6] + (solution[7]*solution[8] / solution[9]) == 87) 
    {
      solutions <- rbind(solutions, solution)
    }
  }
  print("The number of solutions are:")
  print(nrow(solutions)-1)
  return(solutions[2:nrow(solutions),])
}