Synopsis
gawk -f mastermind2.awk [breaker]
Download
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LAWKER.
Description
This is an nteractive play against the evil computer mastermind game.
The game showing the recursive power of the awk language.
It also demonstrates a winning technique for the game mastermind.
The game has two roles, breaker and maker of mastermind codes.
A 5 digit 0 to 9 per digit code must be broken.
The maker responds with one + for every correct digit,position guess
and a - for every correct digit in the wrong position in the code.
A code breaker (human or this program) must use those clues to determine
the code. A score is kept, low score wins.
Example
In the following example, the goal is "12345".
gawk -f mastermind2.awk br
I'll start, I'll break your code, you respond with +-
my guess #1 12413 ++--
my guess #2 12531 ++--
my guess #3 13211 +--
my guess #4 14523 +----
my guess #5 15432 +----
my guess #6 12345 +++++
Code
BEGIN{
srand();
if (index(ARGV[1],"br")) {
print "I'll start, I'll break your code, you respond with +-"
ARGV[1] = ""
mscore += breaker(randguess())
}
do {
printscore()
print "Guess my code 5 digits 0 to 9"
yscore += maker(randguess())
printscore()
print "I'll break your code, you respond with +-"
mscore += breaker(randguess())
} while (1)
}
END{
printscore()
}
function printscore() {
print("\nlow score wins! my score =", mscore, "yours =", yscore)
}
function randguess() {
return incr(int((10*10*10*10*10)*rand()))
}
function smudge(ins,n,ch) {
return substr(ins, 1, n-1) ch substr(ins, n+1)
}
function grade(val, guess, i, rtn, t){
# return + for exact hits, - for "close" for all 5 digits
for (i = 1;i < 6; i++) {
if (substr(val, i, 1) == substr(guess, i, 1)) {
#exact match
rtn = rtn "+"
val = smudge(val, i, "x");
guess = smudge(guess, i, "y");
#print i, val, guess, rtn
}
}
for (i = 1;i < 6; i++) {
t = index(val, substr(guess, i, 1))
if (t) {
rtn = rtn "-"
val = smudge(val, t, "u")
guess = smudge(guess, i, "v");
#print t, i, val, guess, rtn
}
}
return rtn
}
#passed guess and old guess array
#A good guess matches all previous scores with the new guess
function checkguess(g, oldg, i,score) {
#print "guess " g
for (i in oldg) {
if (g == i) return 2 #bad, repeated guess
if (grade(g,i) != oldg[i]) return 1 #reject this guess
}
return 0 #success, this is an ok guess
}
function incr(old, new) {
new = sprintf("%05d",old + 1)
#print "old new", old, new
return substr(new, length(new) -4)
}
function alignres(res, tem) {
for (i=1;i<=length(res);i++) {
if (substr(res, i, 1) == "+") tem = "+" tem
else tem = tem "-"
}
#print "alignres ",res, tem
return tem
}
function breaker(g1, guess, res, hisinput, tries){
guess = g1
do {
printf("my guess #%d %s ", ++tries, guess)
do {
if (getline hisinput <= 0) {
print "whoa, some error, giving up"
exit
}
if (!match(hisinput, /^[-+]*$/)) {
print "invalid response, use only +-"
}
} while (RSTART == 0)
hisinput = alignres(hisinput)
res[guess] = hisinput
#print "hisinput ", hisinput, res[guess]
#for (i in res) print "res[" i "]=" res[i]
if (res[guess] == "+++++") return tries
# make another guess
do {
guess = incr(guess)
r = checkguess(guess, res)
} while (r == 1)
} while (g1 != guess)
print "you must have made a mistake, no answer is possible"
exit
}
function maker(original, his, tries)
{
#print original," cheater!"
do {
if (getline his <= 0) {
print "whoa, some error, giving up"
exit
}
res = grade(original, his)
print "try " ++tries " results",res
if (res == "+++++") return tries
} while (1)
}
See Also
mastermind.awk.
Author
Steve Calfee, USA.
