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Diffstat (limited to 'packages/frontend/src/scripts/shuffle.ts')
| -rw-r--r-- | packages/frontend/src/scripts/shuffle.ts | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/packages/frontend/src/scripts/shuffle.ts b/packages/frontend/src/scripts/shuffle.ts new file mode 100644 index 0000000000..05e6cdfbcf --- /dev/null +++ b/packages/frontend/src/scripts/shuffle.ts @@ -0,0 +1,19 @@ +/** + * 配列をシャッフル (破壊的) + */ +export function shuffle<T extends any[]>(array: T): T { + let currentIndex = array.length, randomIndex; + + // While there remain elements to shuffle. + while (currentIndex !== 0) { + // Pick a remaining element. + randomIndex = Math.floor(Math.random() * currentIndex); + currentIndex--; + + // And swap it with the current element. + [array[currentIndex], array[randomIndex]] = [ + array[randomIndex], array[currentIndex]]; + } + + return array; +} |