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Bombe: Handle boxing stop correctly

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s2224834 2019-02-09 22:57:57 +00:00
parent 61fee3122a
commit 069d4956aa
1 changed files with 28 additions and 6 deletions
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34
src/core/lib/Bombe.mjs
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@ -651,12 +651,34 @@ export class BombeMachine {
// This means our hypothesis for the steckering is correct.
steckerPair = this.testInput[1];
} else {
// If this happens a lot it implies the menu isn't good enough. We can't do
// anything useful with it as we don't have a stecker partner, so we'll just drop it
// and move on. This does risk eating the actual stop occasionally, but I've only seen
// this happen when the menu is bad enough we have thousands of stops, so I'm not sure
// it matters.
return undefined;
// This was known as a "boxing stop" - we have a stop but not a single hypothesis.
// If this happens a lot it implies the menu isn't good enough.
// If we have the checking machine enabled, we're going to just check each wire in
// turn. If we get 0 or 1 hit, great.
// If we get multiple hits, or the checking machine is off, the user will just have to
// deal with it.
if (!this.check) {
// We can't draw any conclusions about the steckering (one could maybe suggest
// options in some cases, but too hard to present clearly).
return [this.indicator.getPos(), "??", this.tryDecrypt("")];
}
let stecker = undefined;
for (let i = 0; i < 26; i++) {
const newStecker = this.checkingMachine(i);
if (newStecker !== "") {
if (stecker !== undefined) {
// Multiple hypotheses can't be ruled out.
return [this.indicator.getPos(), "??", this.tryDecrypt("")];
}
stecker = newStecker;
}
}
if (stecker === undefined) {
// Checking machine ruled all possibilities out.
return undefined;
}
// If we got here, there was just one possibility allowed by the checking machine. Success.
return [this.indicator.getPos(), stecker, this.tryDecrypt(stecker)];
}
let stecker;
if (this.check) {