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Playing a simple guessing game with R. It’s called Mastermind game! This game was originally created for two people, but R version will be for single-player mode, when an R developer or R data scientists need a break.

The gameplay is simple and so are the rules. The board contains 10 rows (or more) with possibilities of four colours and code pegs (white or black). R engine stores a secret colour combination and user selects a random combination.

Based on selection, the R engine returns the black or white pegs. Black peg represents that one colour is at the right place, white that the colour matches, but not the position. No pegs would mean that none of selected colours matches the secret colour combination.

Using x11() function, this game becomes so much fun with R. And the outlooks is:

The game code consists of board function, adding colours on the board, checking for the code pegs function and gameplay function.

```
##########################################
#
# Mastermind board game for R Language
#
# Game for single-player R developers/Data scientists for
# killing time, playing game while waiting for the ML
# model to finish training or just to play.
#
# Series:
# Little Useless-useful R functions #31
# Created: January 06, 2022
# Author: Tomaz Kastrun
# Blog: tomaztsql.wordpress.com
# V.1.0

# Changelog:
###########################################

numberOfColors <- 4
numberOfTries <- 10

get_board <- function(nof_col, nof_try=10){
plot.new()
op <- par(bg = "white")
grid(nx = 6, ny = 12, col = "gray", lty = "dotted",lwd = par("lwd"), equilogs = TRUE)

par(new = TRUE)
plot(c(100,500), c(100,500), xlab = "", ylab = "", xaxt = 'n', yaxt = 'n',main = "Mastermind board game")
nof_tries <- nof_try
for (i in 1:nof_tries) { #rows
for (j in 1:nof_col) { #columns
col <- 50*(1:nof_col-1)
rect(100+col[j], 500-(i*30), 150+col[j], 475-(i*30), col = 'white')
}
}
colours = c('Red','Green','Blue','Yellow','Brown','Orange')
for (z in 1:nof_col) {
rect(100+z*50, 100, 150+z*50, 150, col = colours[z])
}
}

add_rect <- function(colour,try,nof_try=10) {
par(new = TRUE)
max_tries <- numberOfColors*nof_try #10 rows
if (try %% numberOfColors == 0) { #number of tries = number of colours
nof_try <- try/numberOfColors
}

if (try > numberOfColors){
row <- ceiling((try/numberOfColors))
rect_order <- abs(try-((row-1)*numberOfColors))
} else {
row <- 1
rect_order <- try
}
rect(100+(rect_order*50)-50, 500-(row*30),150+((rect_order*50))-50, 475-(row*30), col = colour)
}

add_key_pegs <- function(input_colours, store_secret,nof_try){

ss <- store_secret
ic <- input_colours
ss1 <- as.vector(strsplit(as.character(ss), "")[[1]])
ic1 <- as.vector(strsplit(as.character(ic), "")[[1]])

white <- ""
black <- ""
for (i in 1:length(ss1)){
for (j in 1:length(ic1)){
if (i==j && ss1[i] == ic1[j]) {black <- as.integer(paste( c(black, ic1[j]),collapse=""))}
if (ss1[i] == ic1[j]) { white <- as.integer(paste( c(white, ic1[j]),collapse="")) }
}
}

black1 <- as.vector(strsplit(as.character(black), "")[[1]])
white1 <- as.vector(strsplit(as.character(white), "")[[1]])

black <- nchar(black)
white <- length(unique(setdiff(white1, black1)))
nof_tokes <- black + white
tok <- replicate(black, "black")
en <- replicate(white, "gray")
token <- c(tok, en)
name1 <- token[1]
name2 <- token[2]
name3 <- token[3]
name4 <- token[4]

if (nof_tokes == 1) {
par(new = TRUE)
plot(450,500-(nof_try*30), col = name1, lwd = 2, xaxt = 'n', yaxt = 'n', xlab = "",ylab = "",xlim=range(100:500), ylim=range(100:500))
}
if (nof_tokes == 2) {
par(new = TRUE)
plot(450,500-(nof_try*30), col = name1, lwd = 2, xaxt = 'n', yaxt = 'n', xlab = "",ylab = "",xlim=range(100:500), ylim=range(100:500))
par(new = TRUE)
plot(450,490-(nof_try*30), col = name2, lwd = 2, xaxt = 'n', yaxt = 'n', xlab = "",ylab = "",xlim=range(100:500), ylim=range(100:500))
}
if (nof_tokes == 3) {
par(new = TRUE)
plot(450,500-(nof_try*30), col = name1, lwd = 2, xaxt = 'n', yaxt = 'n', xlab = "",ylab = "",xlim=range(100:500), ylim=range(100:500))
par(new = TRUE)
plot(450,490-(nof_try*30), col = name2, lwd = 2, xaxt = 'n', yaxt = 'n', xlab = "",ylab = "",xlim=range(100:500), ylim=range(100:500))
par(new = TRUE)
plot(470,500-(nof_try*30), col = name3, lwd = 2, xaxt = 'n', yaxt = 'n', xlab = "",ylab = "",xlim=range(100:500), ylim=range(100:500))
}
if (nof_tokes == 4) {
par(new = TRUE)
plot(450,500-(nof_try*30), col = name1, lwd = 2, xaxt = 'n', yaxt = 'n', xlab = "",ylab = "",xlim=range(100:500), ylim=range(100:500))
par(new = TRUE)
plot(450,490-(nof_try*30), col = name2, lwd = 2, xaxt = 'n', yaxt = 'n', xlab = "",ylab = "",xlim=range(100:500), ylim=range(100:500))
par(new = TRUE)
plot(470,500-(nof_try*30), col = name3, lwd = 2, xaxt = 'n', yaxt = 'n', xlab = "",ylab = "",xlim=range(100:500), ylim=range(100:500))
par(new = TRUE)
plot(470,490-(nof_try*30), col = name4, lwd = 2, xaxt = 'n', yaxt = 'n', xlab = "",ylab = "",xlim=range(100:500), ylim=range(100:500))
}
}

get_secret <- function(nof_col, colours_repeat=FALSE) {
colours <- c(1:4)
s <- sample(colours,nof_col, replace=colours_repeat)
s <- paste(s, collapse="")
return(as.integer(s))
}

game <- function(numberOfColors=4, numberOfTries=10){
rm(list = ls())
x11()
end_game <- 1
count <<- 0
get_board(nof_col = numberOfColors, nof_try = numberOfTries)
store_secret <<- get_secret(nof_col=numberOfColors, colours_repeat =TRUE)
input_colours <<- 0L
#input_colours <- c("Blue", "Yellow","Green","Yellow") #, "Brown", "Green")
nof_selection <- numberOfColors
max_tries <- nof_selection*numberOfTries

while (end_game <= max_tries && store_secret != input_colours) {
mouse.at <- locator(n = 1, type = "o")
x.at <- mouse.at\$x
y.at <- mouse.at\$y

if (x.at >= 150 & x.at < 200 & y.at >= 100 & y.at <=150) {
input_colours <<- as.integer(paste( c(input_colours, 1),collapse=""))
}
if (x.at >= 200 & x.at < 250 & y.at >= 100 & y.at <=150) {
input_colours <<- as.integer(paste( c(input_colours, 2),collapse=""))
}
if (x.at >= 250 & x.at < 300 & y.at >= 100 & y.at <=150) {
input_colours <<- as.integer(paste( c(input_colours, 3),collapse=""))
}
if (x.at >= 300 & x.at < 350 & y.at >= 100 & y.at <=150) {
input_colours <<- as.integer(paste( c(input_colours, 4),collapse=""))
}

#end game if needed
if (store_secret == input_colours) {
par(new = TRUE)
mtext("GAME WON", side=1)
break
}

#end game if needed
if (end_game == max_tries) {
par(new = TRUE)
mtext("END GAME", side=1)
}

if (end_game %% numberOfColors == 0)  {
input_colours <<- 0L
count <<- count + 1
print(count)

}
# increment next level
end_game = end_game + 1
}

}

######################
### Start The game ###
######################

game()

```

And a simple gameplay:

As always, code is available in at the Github in same Useless_R_function repository and the R file to the game is in the same repository, here. Check Github for future updates.

Happy R-coding and stay healthy!