[์ž๋ฐ” ์•Œ๊ณ ๋ฆฌ์ฆ˜ ๋ฌธ์ œํ’€์ด] ๊ฐ€์žฅ ๊ธด ๋‹จ์–ด ์ฐพ๊ธฐ / .split(), indexOf(), substring()

๐Ÿ”’ ์ž๋ฐ” ์•Œ๊ณ ๋ฆฌ์ฆ˜ ๋ฌธ์ œํ’€์ด ๐Ÿ” ๊ฐ€์žฅ ๊ธด ๋‹จ์–ด ์ฐพ๊ธฐ ๋ฌธ์žฅ์„ ์ž…๋ ฅ ๋ฐ›๊ณ , ๊ฐ€์žฅ ๊ธด ๋‹จ์–ด๋ฅผ ์ฐพ์•„๋ณด์ž. (๋‹จ, ๊ฐ™์€ ๊ธธ์ด์˜ ๋‹จ์–ด๊ฐ€ ์—ฌ๋Ÿฌ๊ฐœ์ผ ๊ฒฝ์šฐ, ์ œ์ผ ์•ž์ชฝ์— ์œ„์น˜ํ•œ ๋‹จ์–ด ์ถœ๋ ฅ) ๐Ÿ”“ split() ์ด์šฉํ•˜๊ธฐ import java.util.Scanner; public class Main { public String solution(String str){ String answer = ""; int max = 0; String[] s... Continue reading...

[์ž๋ฐ” ์•Œ๊ณ ๋ฆฌ์ฆ˜ ๋ฌธ์ œํ’€์ด] ๋Œ€์†Œ๋ฌธ์ž ๋ณ€ํ™˜ํ•˜๊ธฐ

๐Ÿ”’ ์ž๋ฐ” ์•Œ๊ณ ๋ฆฌ์ฆ˜ ๋ฌธ์ œํ’€์ด ๐Ÿ” ๋Œ€์†Œ๋ฌธ์ž ๋ณ€ํ™˜ํ•˜๊ธฐ ์ž…๋ ฅ๋ฐ›์€ ๋Œ€๋ฌธ์ž๋ฅผ ์†Œ๋ฌธ์ž๋กœ, ์†Œ๋ฌธ์ž๋ฅผ ๋Œ€๋ฌธ์ž๋กœ ๋ฐ”๊ฟ”๋ณด์ž. ๐Ÿ”“ toUpperCase() / to LowerCase() ์ด์šฉํ•˜๊ธฐ import java.util.Scanner; public class Main { public String solution(String str){ String answer = ""; for (char ch : str.toCharArray()) { if (Character.isLowerCase(ch)){ answer += Character.toUpperCase(ch); } else { answer += Character.toLowerCase(ch);... Continue reading...

[์ž๋ฐ” ์•Œ๊ณ ๋ฆฌ์ฆ˜ ๋ฌธ์ œํ’€์ด] ํŠน์ • ๋ฌธ์ž ๊ฐœ์ˆ˜ ์ฐพ๊ธฐ

๐Ÿ”’ ์ž๋ฐ” ์•Œ๊ณ ๋ฆฌ์ฆ˜ ๋ฌธ์ œํ’€์ด ๐Ÿ” ํŠน์ • ๋ฌธ์ž ๊ฐœ์ˆ˜ ์ฐพ๊ธฐ ๋ฌธ์ž์—ด์„ ์ž…๋ ฅ ๋ฐ›๊ณ , ํŠน์ • ๋ฌธ์ž์˜ ๊ฐœ์ˆ˜๋ฅผ ์ฐพ์•„๋ณด์ž. (+ ํ–ฅ์ƒ๋œ for๋ฌธ ์‚ฌ์šฉ) import java.util.Scanner; public class Main { public int solution(String str, char ch){ int answer = 0; str = str.toUpperCase(); ch = Character.toUpperCase(ch); for(char x : str.toCharArray()) { if (x ==... Continue reading...

[์ •์ฒ˜๊ธฐ ํ•„๊ธฐ] ์˜ค๋‹ต๋…ธํŠธ) ์†Œํ”„ํŠธ์›จ์–ด ํ’ˆ์งˆ ํŠน์„ฑ / DBMS์˜ ํ•„์ˆ˜ ๊ธฐ๋Šฅ

๐Ÿคทโ€โ™€๏ธ ์ •์ฒ˜๊ธฐ ํ•„๊ธฐ ์˜ค๋‹ต๋…ธํŠธ โœ… ์†Œํ”„ํŠธ์›จ์–ด ํ’ˆ์งˆ ํŠน์„ฑ Q. ์†Œํ”„ํŠธ์›จ์–ด ํ’ˆ์งˆ ๋ชฉํ‘œ ์ค‘ ํ’ˆ์งˆ ๋ถ€ํŠน์„ฑ์œผ๋กœ ์‹œ๊ฐ„๋ฐ˜์‘์„ฑ, ์ž์›ํšจ์œจ์„ฑ, ์ค€์ˆ˜์„ฑ ๋“ฑ์„ ๊ฐ–๋Š” ๊ฒƒ์€? โ‘  ๋ฌด๊ฒฐ์„ฑ(Integrity) โ‘ก ์œ ์—ฐ์„ฑ(Flexibility) โ‘ข ํšจ์œจ์„ฑ(Efficiency) โ‘ฃ ์‹ ๋ขฐ์„ฑ(Reliability) ์ •๋‹ต : โ‘ข ๐Ÿ”Ž ISO/IEC 9126์˜ ์†Œํ”„ํŠธ์›จ์–ด ํ’ˆ์งˆ ํŠน์„ฑ ๊ธฐ๋Šฅ์„ฑ(Functionality) / ์‹ ๋ขฐ์„ฑ(Reliability) / ์‚ฌ์šฉ์„ฑ(Usability) / ํšจ์œจ์„ฑ(Efficiency) / ์œ ์ง€๋ณด์ˆ˜์„ฑ(Maintainability) / ์ด์‹์„ฑ(Portability) ํšจ์œจ์„ฑ(Efficiency)... Continue reading...

[์ •์ฒ˜๊ธฐ ํ•„๊ธฐ] ์˜ค๋‹ต๋…ธํŠธ) ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค ๋ฌด๊ฒฐ์„ฑ / ๋ฐ์ดํ„ฐ ๋ชจ๋ธ / ๋ฐ์ดํ„ฐ ๋ชจ๋ธ ์ ˆ์ฐจ / ํ›„๋ณด ํ‚ค / ์ ‘๊ทผ ์ œ์–ด ์ •์ฑ…

๐Ÿคทโ€โ™€๏ธ ์ •์ฒ˜๊ธฐ ํ•„๊ธฐ ์˜ค๋‹ต๋…ธํŠธ โœ… ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค ๋ฌด๊ฒฐ์„ฑ Q. ํ•œ ๋ฆด๋ ˆ์ด์…˜์˜ ๊ธฐ๋ณธ ํ‚ค๋ฅผ ๊ตฌ์„ฑํ•˜๋Š” ์–ด๋– ํ•œ ์†์„ฑ๊ฐ’๋„ ๋„(NULL)๊ฐ’์ด๋‚˜ ์ค‘๋ณต๊ฐ’์„ ๊ฐ€์งˆ ์ˆ˜ ์—†์Œ์„ ์˜๋ฏธํ•˜๋Š” ๋ฌด๊ฒฐ์„ฑ์˜ ์ข…๋ฅ˜๋Š”? โ‘  ๊ฐœ์ฒด ๋ฌด๊ฒฐ์„ฑ โ‘ก ์ฐธ์กฐ ๋ฌด๊ฒฐ์„ฑ โ‘ข ๋„๋ฉ”์ธ ๋ฌด๊ฒฐ์„ฑ โ‘ฃ ํ‚ค ๋ฌด๊ฒฐ์„ฑ ์ •๋‹ต : โ‘  ๐Ÿ”Ž ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค ๋ฌด๊ฒฐ์„ฑ(Database Integrity) ๊ฐœ์ฒด ๋ฌด๊ฒฐ์„ฑ : ํ•œ ์—”ํ„ฐํ‹ฐ์—์„œ ๋™์ผํ•œ ๊ธฐ๋ณธ ํ‚ค(PK)๋ฅผ... Continue reading...