28 lines
617 B
TypeScript
28 lines
617 B
TypeScript
/**
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* Shuffles array in place.
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* @param {Array} a items An array containing the items.
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*/
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export function shuffle<T>(a: T[]): T[] {
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let j, x, i;
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let b = Array.from(a);
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for (i = b.length - 1; i > 0; i--) {
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j = Math.floor(Math.random() * (i + 1));
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x = b[i];
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b[i] = b[j];
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b[j] = x;
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}
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return b;
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}
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export function randint(n: number) {
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return Math.floor(Math.random() * n);
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}
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export function choice<T>(arr: readonly T[]): T {
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return arr[randint(arr.length)];
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}
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export function range(n: number): number[] {
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return Array.from({length: n}, (x, i) => i);
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}
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