๋ณธ๋ฌธ ๋ฐ”๋กœ๊ฐ€๊ธฐ

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[๊ฐœ๋… ์ •๋ฆฌ] ํˆฌ ํฌ์ธํ„ฐ ์ตœ๊ทผ ์•Œ๊ณ ๋ฆฌ์ฆ˜์„ ํ’€๋ฉด์„œ ์‹œ๊ฐ„ ์ดˆ๊ณผ์™€ ์˜ˆ์™ธ์ฒ˜๋ฆฌ๋กœ ์ธํ•ด ์ƒ๋‹นํžˆ ์• ๋ฅผ ๋จน์—ˆ๋˜ ๋ฌธ์ œ๊ฐ€ ์žˆ๋‹ค. ํ•ด๋‹น ๋ฌธ์ œ์˜ ๋‹ค๋ฅธ ํ’€์ด๋ฅผ ์ฐพ์•„๋ณด๋‹ˆ ํˆฌ ํฌ์ธํ„ฐ ์•Œ๊ณ ๋ฆฌ์ฆ˜์„ ํ†ตํ•ด ๊ฐ„๋‹จํ•˜๊ฒŒ ๊ตฌํ˜„ํ•  ์ˆ˜ ์žˆ๋‹ค๋Š” ์ ์„ ์•Œ์•˜๊ณ  ์ด์— ๋Œ€ํ•ด ์ •๋ฆฌํ•ด๋ณด๊ณ ์ž ํ•œ๋‹ค. ํˆฌ ํฌ์ธํ„ฐ ์•Œ๊ณ ๋ฆฌ์ฆ˜์€ ํ•˜๋‚˜์˜ ๋ฐฐ์—ด์—์„œ ๋‘ ๊ฐœ์˜ ์ธ๋ฑ์Šค ํฌ์ธํ„ฐ๋ฅผ ์กฐ์ž‘ํ•˜๋Š” ์•Œ๊ณ ๋ฆฌ์ฆ˜์„ ์˜๋ฏธํ•œ๋‹ค. ๋ฌธ์ œ๋ฅผ ์˜ˆ์‹œ๋กœ ๋“ค์–ด์„œ ์„ค๋ช…ํ•˜๋ฉด ๋‹ค์Œ๊ณผ ๊ฐ™๋‹ค. ๋ฐฑ์ค€ - 2467. ์šฉ์•ก ์ด ๋ฌธ์ œ์—์„œ 0๊ณผ ๊ฐ€์žฅ ๊ฐ€๊นŒ์šด ๊ฑฐ๋ฆฌ์˜ ํ•ฉ์„ ๊ฐ€์ง€๋Š” ๋‘ ์›์†Œ๋ฅผ ๊ตฌํ•˜๋Š” ๋ฐฉ๋ฒ•์€ ๋จผ์ € O(N^2)์˜ ์‹œ๊ฐ„๋ณต์žก๋„๋ฅผ ๊ฐ€์ง€๋Š” ๋ฐฉ๋ฒ•์ด ์กด์žฌํ•œ๋‹ค. ํ•˜์ง€๋งŒ ๋ฌธ์ œ์ฒ˜๋Ÿผ N์˜ ํฌ๊ธฐ๊ฐ€ O(N^2)์œผ๋กœ ํ•ด๊ฒฐํ•  ์ˆ˜ ์—†๋Š” ๊ฒฝ์šฐ์— ํˆฌ ํฌ์ธํ„ฐ ์•Œ๊ณ ๋ฆฌ์ฆ˜์„ ์‚ฌ์šฉํ•˜๋ฉด O(N)์— ํ•ด๋‹น ๊ฐ’์„ ๊ตฌํ•  ์ˆ˜ ์žˆ๋‹ค. (์ด ๋ฌธ์ œ๋Š” ์ •๋ ฌ์ด ํ•„์š”ํ•˜๊ธฐ ๋•Œ๋ฌธ์— ์ „์ฒด ๋ฌธ์ œ์˜ ์‹œ๊ฐ„๋ณต์žก๋„๋Š” O(.. 2021. 4. 1.