68 lines
1.3 KiB
TypeScript
68 lines
1.3 KiB
TypeScript
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/**
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* Time: 7 15 30
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* Distance: 9 40 200
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*/
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const example = [
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{
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time: 7,
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distance: 9
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},
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{
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time: 15,
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distance: 40
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},
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{
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time: 30,
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distance: 200
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}
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]
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/**
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* Time: 58 99 64 69
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* Distance: 478 2232 1019 1071
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*/
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const input = [
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{
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time: 58,
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distance: 478
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},
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{
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time: 99,
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distance: 2232
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},
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{
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time: 64,
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distance: 1019
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},
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{
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time: 69,
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distance: 1071
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}
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]
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function caculRangeOfBeatRecord(time: number, distance: number) {
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const mid = time / 2;
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const dist = Math.sqrt(Math.pow(time, 2) / 4 - distance);
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return {
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start: mid - dist, // include
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end: mid + dist, // exclude
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}
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}
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/**
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* count natrual numbers in the range. it could be real number.
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* @param {number} start
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* @param {number} end
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* @returns natrual numbers in the range
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*/
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function countRange(start: number, end: number) {
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return Math.ceil(end - 1) - Math.floor(start + 1) + 1
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}
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const res = input.map(e => {
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const range = caculRangeOfBeatRecord(e.time, e.distance);
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const count = countRange(range.start, range.end);
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console.log(range, count)
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return count;
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}).reduce((a, b) => a * b, 1);
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console.log(res);
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