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๐Ÿ“ƒ SQL Schema & Catalog

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SQL Schema

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๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค๋ผ๊ณ ๋„ ๋ถˆ๋ฆฌ๋ฉฐ, ๊ฐ™์€ ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค์— ์†ํ•ด ์žˆ๋Š” ํ…Œ์ด๋ธ”๊ณผ ๋‹ค๋ฅธ ๊ตฌ์กฐ๋“ค์„ ๊ทธ๋ฃน์ง“๋Š” ๊ฐœ๋…์ด๋‹ค.
\nSchema name์œผ๋กœ ๊ตฌ๋ณ„๋œ๋‹ค.
\n์Šคํ‚ค๋งˆ๋ฅผ ์†Œ์œ ํ•˜๋Š” ์‚ฌ์šฉ์ž๋ฅผ ๋‚˜ํƒ€๋‚ด๋Š” authorization identifier์™€ ์Šคํ‚ค๋งˆ์— ์žˆ๋Š” ๊ฐ๊ฐ element์˜ descriptor๋ฅผ ํฌํ•จํ•œ๋‹ค.
\nSchema element๋Š” table, constraints, views, domains ๋“ฑ์„ ํฌํ•จํ•œ๋‹ค.

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CREATE SCHEMA COMPANY AUTHORIZATION 'Joshua'
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Catalog

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์Šคํ‚ค๋งˆ์˜ ๋ชจ์ž„์œผ๋กœ, INFORMATION_SCHEMA ๋ผ๊ณ  ๋ถˆ๋ฆฌ๋Š” ํŠน๋ณ„ํ•œ ์Šคํ‚ค๋งˆ๋ฅผ ํ•ญ์ƒ ๊ฐ€์ง€๊ณ  ์žˆ๋‹ค.
\nIntegrity constraints๋Š” ๊ฐ™์€ catalog์˜ ์Šคํ‚ค๋งˆ๋“ค ์‚ฌ์ด์—์„œ๋งŒ ์ •์˜๋  ์ˆ˜ ์žˆ๋‹ค.
\n๊ฐ™์€ catalog์— ์žˆ๋Š” ์Šคํ‚ค๋งˆ๋“ค์€ type/domain๊ณผ ๊ฐ™์€ ํŠน์ • element๋ฅผ ๊ณต์œ ํ•  ์ˆ˜ ์žˆ๋‹ค.

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๐Ÿ“š CREATE TABLE

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์ƒˆ๋กœ์šด relation R์„ ์ •์˜ํ•œ๋‹ค.
\nR์— ์ด๋ฆ„์„ ์ฃผ๊ณ ๋‚˜์„œ, R์˜ attributes์™€ types(domains), ์ดˆ๊ธฐ ์ œ์•ฝ์กฐ๊ฑด๋“ค(NOT NULL or UNIQUE) ์„ ์ •์˜ํ•œ๋‹ค.
\nkey, ์—”ํ„ฐํ‹ฐ ๋ฌด๊ฒฐ์„ฑ, ์ฐธ์กฐ ๋ฌด๊ฒฐ์„ฑ ์ œ์•ฝ์กฐ๊ฑด๋“ค์€ attribute ์„ ์–ธ ์ดํ›„์— ์ •์˜ํ•  ์ˆ˜ ์žˆ๋‹ค.
\n(ํ…Œ์ด๋ธ” ์ƒ์„ฑ ํ›„์—๋„ ALTER TABLE ์„ ์‚ฌ์šฉํ•ด์„œ ์ถ”๊ฐ€ํ•  ์ˆ˜ ์žˆ์Œ)

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CREATE TABLE EMPLOYEE \n{\n...\n}
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ALTER TABLE EMPLOYEE ADD FOREIGN KEY (Super_ssn) REFERENCES EMPLOYEE(Ssn);
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๐Ÿงฉ Attribute์˜ Data Type๊ณผ Domain

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๐Ÿšง SQL ์ œ์•ฝ์กฐ๊ฑด ์„ค์ •

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","excerpt":"๐Ÿ“ƒ SQL Schema & Catalog SQL Schema ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค๋ผ๊ณ ๋„ ๋ถˆ๋ฆฌ๋ฉฐ, ๊ฐ™์€ ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค์— ์†ํ•ด ์žˆ๋Š” ํ…Œ์ด๋ธ”๊ณผ ๋‹ค๋ฅธ ๊ตฌ์กฐ๋“ค์„ ๊ทธ๋ฃน์ง“๋Š” ๊ฐœ๋…์ด๋‹ค. Schema name์œผ๋กœ ๊ตฌ๋ณ„๋œ๋‹ค. ์Šคํ‚ค๋งˆ๋ฅผ ์†Œ์œ ํ•˜๋Š” ์‚ฌ์šฉ์ž๋ฅผ ๋‚˜ํƒ€๋‚ด๋Š” authorization identifier์™€ ์Šคํ‚ค๋งˆ์— ์žˆ๋Š” ๊ฐ๊ฐ element์˜ descriptor๋ฅผ ํฌํ•จํ•œ๋‹ค. Schema element๋Š” table, constraints, views, domains ๋“ฑ์„ ํฌํ•จํ•œ๋‹ค. Catalog ์Šคํ‚ค๋งˆ์˜ ๋ชจ์ž„์œผ๋กœ, ๋ผ๊ณ  ๋ถˆ๋ฆฌ๋Š” ํŠน๋ณ„ํ•œ ์Šคํ‚ค๋งˆ๋ฅผ ํ•ญ์ƒ ๊ฐ€์ง€๊ณ  ์žˆ๋‹ค. Integrity constraints๋Š” ๊ฐ™์€ catalog์˜ ์Šคํ‚ค๋งˆ๋“ค ์‚ฌ์ด์—์„œ๋งŒ ์ •์˜๋  ์ˆ˜ ์žˆ๋‹ค. ๊ฐ™์€ catalog์— ์žˆ๋Š” ์Šคํ‚ค๋งˆ๋“ค์€ type/domain๊ณผ ๊ฐ™์€ ํŠน์ • element๋ฅผ ๊ณต์œ ํ•  ์ˆ˜ ์žˆ๋‹ค. ๐Ÿ“š CREATE TABLE ์ƒˆ๋กœ์šด relation R์„ ์ •์˜ํ•œ๋‹ค. R์— ์ด๋ฆ„์„ ์ฃผ๊ณ ๋‚˜์„œ, R์˜ attributes์™€ types(domains), ์ดˆ๊ธฐโ€ฆ","frontmatter":{"date":"December 08, 2021","title":"[Database] SQL ๊ธฐ์ดˆ","categories":"Database","author":"JFe","emoji":"๐Ÿซ"},"fields":{"slug":"/db-sql-basic/"}},"next":{"id":"94a97aa8-5de8-590c-94a7-d3f25beca2c3","html":"

๐Ÿ—บ ER-to-Relational Mapping

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Step 1. Regular Entity Types

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๊ธฐ์กด ์—”ํ„ฐํ‹ฐ์˜ attribute๋ฅผ ์ „๋ถ€ ํฌํ•จํ•˜๊ณ , key attributes ์ค‘์—์„œ ํ•˜๋‚˜๋ฅผ ๊ณจ๋ผ Primary key๋กœ ์ •ํ•œ๋‹ค.
\n๋งŒ์•ฝ, ๊ณ ๋ฅธ key๊ฐ€ composite์ด๋ฉด ํ•ด๋‹นํ•˜๋Š” attribute๋“ค ๋ชจ๋‘ Primary key๋กœ ์ •ํ•œ๋‹ค.

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Step 2. Weak Entity Types

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weak ์—”ํ„ฐํ‹ฐ์˜ attribute๋ฅผ ์ „๋ถ€ ํฌํ•จ
\nowner ์—”ํ„ฐํ‹ฐ์˜ Primary key๋ฅผ Foreign key๋กœ ๊ฐ€์ง€๊ณ ,
\nowner ์—”ํ„ฐํ‹ฐ์˜ Primary key์™€ weak ์—”ํ„ฐํ‹ฐ์˜ Partial key๋ฅผ Primary key๋กœ ๊ฐ€์ง„๋‹ค.

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Step 3. Binary 1:1 Relation Types

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์ƒํ™ฉ์— ๋”ฐ๋ผ 3๊ฐ€์ง€ ๋ฐฉ๋ฒ•์œผ๋กœ ๊ฐ€๋Šฅํ•˜๋‹ค.

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1. Foreign key approach (2 relations)

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์ฃผ๋กœ ํ•œ์ชฝ์ด total participation์ผ ๋•Œ ์‚ฌ์šฉ
\ntotal participation์ธ ์ชฝ์„ S, ๋ฐ˜๋Œ€๋ฅผ T๋กœ ๋‘๋ฉด, T์˜ Primary key์— ํ•ด๋‹นํ•˜๋Š” Foreign key๋ฅผ S์— ๋งŒ๋“ค์–ด์„œ ์„œ๋กœ ์—ฐ๊ฒฐ์‹œํ‚จ๋‹ค.

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2. Merged relation (1 relation)

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๋‘˜๋‹ค total participation์ธ ๊ฒฝ์šฐ์—, ๋‘ entity๋ฅผ ํ•˜๋‚˜์˜ relation์œผ๋กœ ํ•ฉ์นœ๋‹ค.

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3. Cross-reference or relationship relation (3 relations)

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์„ธ ๋ฒˆ์งธ relation U๋ฅผ ๋งŒ๋“ค์–ด์„œ S, T์™€ ์—ฐ๊ฒฐ
\nS์™€ T์˜ Foreign key ์ค‘ ํ•˜๋‚˜๋ฅผ U์˜ Primary key๋กœ ๋งŒ๋“ค๊ณ , ๋‚˜๋จธ์ง€ Foreign key ํ•˜๋‚˜๋Š” U์˜ Unique key๋กœ ๋งŒ๋“ ๋‹ค.
\n์ถ”๊ฐ€์ ์ธ join operation์ด ํ•„์š”

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Step 4. Binary 1:N Relation Types

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1-side์˜ Primary key๋ฅผ N-side์— Foreign key๋กœ ๊ฐ€์ง€๊ณ  ์„œ๋กœ ์—ฐ๊ฒฐ์‹œํ‚จ๋‹ค.

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Step 5. Binary M:N Relation Types

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relationship relation์ด๋ผ ๋ถˆ๋ฆฌ๋Š” ์ƒˆ๋กœ์šด relation U๋ฅผ ์ƒ์„ฑ
\n๊ฐ๊ฐ ์—”ํ„ฐํ‹ฐ์—์„œ Primary key๋“ค์„ ๋ฝ‘์•„์„œ U์˜ Foreign key๋กœ ๋งŒ๋“ค๊ณ  ์„œ๋กœ ์—ฐ๊ฒฐ
\n์ด ๋•Œ, ์ด key๋“ค์€ U์˜ Primary key๊ฐ€ ๋œ๋‹ค.

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Step 6. Multivalued attributes

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multivalued attribute A์— ๋Œ€ํ•ด์„œ, ์ƒˆ๋กœ์šด relation U๋ฅผ ๋งŒ๋“ ๋‹ค.
\nU์˜ Foreign key๋กœ๋Š”, ์›๋ž˜ A attribute๊ฐ€ ์†ํ–ˆ๋˜ entity์˜ Primary key๋ฅผ Foreign key๋กœ ๊ฐ€์ง„๋‹ค.
\nU์˜ Primary key๋กœ๋Š”, ์œ„์— ์–˜๊ธฐํ•œ Foreign key์™€ ์›๋ž˜ attribute A, ์ด๋ ‡๊ฒŒ ๋‘˜์„ Primary key๋กœ ๊ฐ€์ง„๋‹ค.

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Step 7. N-ary Relationship Types

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N-ary relationship type R์—์„œ n > 2 ๋ฉด, ์ƒˆ๋กœ์šด relationship relation U๋ฅผ ์ƒ์„ฑ
\n์ฐธ์—ฌํ•˜๋Š” ๋ชจ๋“  entity์˜ Primary key๋“ค์„ U์˜ Foreign key๋กœ ๊ฐ€์ง„๋‹ค.

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","frontmatter":{"date":"December 07, 2021","title":"[Database] ER-to-Relational Mapping","categories":"Database","author":"JFe","emoji":"๐Ÿ—บ"},"fields":{"slug":"/db-er-to-relational/"}},"prev":{"id":"c55b1096-8008-58dc-9dbc-56d197234a24","html":"

๋ฌธ์ œ

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https://www.acmicpc.net/problem/17779

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์žฌํ˜„์‹œ์˜ ์‹œ์žฅ ๊ตฌ์žฌํ˜„์€ ์ง€๋‚œ ๋ช‡ ๋…„๊ฐ„ ๊ฒŒ๋ฆฌ๋งจ๋”๋ง์„ ํ†ตํ•ด์„œ ์ž์‹ ์˜ ๋‹น์—๊ฒŒ ์œ ๋ฆฌํ•˜๊ฒŒ ์„ ๊ฑฐ๊ตฌ๋ฅผ ํš์ •ํ–ˆ๋‹ค. ๊ฒฌ์ œํ•  ๊ถŒ๋ ฅ์ด ์—†์–ด์ง„ ๊ตฌ์žฌํ˜„์€ ๊ถŒ๋ ฅ์„ ๋งค์šฐ ๋ถ€๋‹นํ•˜๊ฒŒ ํ–‰์‚ฌํ–ˆ๊ณ , ์‹ฌ์ง€์–ด๋Š” ์‹œ์˜ ์ด๋ฆ„๋„ ์žฌํ˜„์‹œ๋กœ ๋ณ€๊ฒฝํ–ˆ๋‹ค. ์ด๋ฒˆ ์„ ๊ฑฐ์—์„œ๋Š” ์ตœ๋Œ€ํ•œ ๊ณตํ‰ํ•˜๊ฒŒ ์„ ๊ฑฐ๊ตฌ๋ฅผ ํš์ •ํ•˜๋ ค๊ณ  ํ•œ๋‹ค.

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์žฌํ˜„์‹œ๋Š” ํฌ๊ธฐ๊ฐ€ Nร—N์ธ ๊ฒฉ์ž๋กœ ๋‚˜ํƒ€๋‚ผ ์ˆ˜ ์žˆ๋‹ค. ๊ฒฉ์ž์˜ ๊ฐ ์นธ์€ ๊ตฌ์—ญ์„ ์˜๋ฏธํ•˜๊ณ , rํ–‰ c์—ด์— ์žˆ๋Š” ๊ตฌ์—ญ์€ (r, c)๋กœ ๋‚˜ํƒ€๋‚ผ ์ˆ˜ ์žˆ๋‹ค. ๊ตฌ์—ญ์„ ๋‹ค์„ฏ ๊ฐœ์˜ ์„ ๊ฑฐ๊ตฌ๋กœ ๋‚˜๋ˆ ์•ผ ํ•˜๊ณ , ๊ฐ ๊ตฌ์—ญ์€ ๋‹ค์„ฏ ์„ ๊ฑฐ๊ตฌ ์ค‘ ํ•˜๋‚˜์— ํฌํ•จ๋˜์–ด์•ผ ํ•œ๋‹ค. ์„ ๊ฑฐ๊ตฌ๋Š” ๊ตฌ์—ญ์„ ์ ์–ด๋„ ํ•˜๋‚˜ ํฌํ•จํ•ด์•ผ ํ•˜๊ณ , ํ•œ ์„ ๊ฑฐ๊ตฌ์— ํฌํ•จ๋˜์–ด ์žˆ๋Š” ๊ตฌ์—ญ์€ ๋ชจ๋‘ ์—ฐ๊ฒฐ๋˜์–ด ์žˆ์–ด์•ผ ํ•œ๋‹ค. ๊ตฌ์—ญ A์—์„œ ์ธ์ ‘ํ•œ ๊ตฌ์—ญ์„ ํ†ตํ•ด์„œ ๊ตฌ์—ญ B๋กœ ๊ฐˆ ์ˆ˜ ์žˆ์„ ๋•Œ, ๋‘ ๊ตฌ์—ญ์€ ์—ฐ๊ฒฐ๋˜์–ด ์žˆ๋‹ค๊ณ  ํ•œ๋‹ค. ์ค‘๊ฐ„์— ํ†ตํ•˜๋Š” ์ธ์ ‘ํ•œ ๊ตฌ์—ญ์€ 0๊ฐœ ์ด์ƒ์ด์–ด์•ผ ํ•˜๊ณ , ๋ชจ๋‘ ๊ฐ™์€ ์„ ๊ฑฐ๊ตฌ์— ํฌํ•จ๋œ ๊ตฌ์—ญ์ด์–ด์•ผ ํ•œ๋‹ค.

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์„ ๊ฑฐ๊ตฌ๋ฅผ ๋‚˜๋ˆ„๋Š” ๋ฐฉ๋ฒ•์€ ๋‹ค์Œ๊ณผ ๊ฐ™๋‹ค.

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  1. ๊ธฐ์ค€์  (x, y)์™€ ๊ฒฝ๊ณ„์˜ ๊ธธ์ด d1, d2๋ฅผ ์ •ํ•œ๋‹ค. (d1, d2 โ‰ฅ 1, 1 โ‰ค x < x+d1+d2 โ‰ค N, 1 โ‰ค y-d1 < y < y+d2 โ‰ค N)
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  2. ๋‹ค์Œ ์นธ์€ ๊ฒฝ๊ณ„์„ ์ด๋‹ค.\n
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    1. (x, y), (x+1, y-1), โ€ฆ, (x+d1, y-d1)
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    2. (x, y), (x+1, y+1), โ€ฆ, (x+d2, y+d2)
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    3. (x+d1, y-d1), (x+d1+1, y-d1+1), โ€ฆ (x+d1+d2, y-d1+d2)
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    4. (x+d2, y+d2), (x+d2+1, y+d2-1), โ€ฆ, (x+d2+d1, y+d2-d1)
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  3. ๊ฒฝ๊ณ„์„ ๊ณผ ๊ฒฝ๊ณ„์„ ์˜ ์•ˆ์— ํฌํ•จ๋˜์–ด์žˆ๋Š” ๊ณณ์€ 5๋ฒˆ ์„ ๊ฑฐ๊ตฌ์ด๋‹ค.
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  4. 5๋ฒˆ ์„ ๊ฑฐ๊ตฌ์— ํฌํ•จ๋˜์ง€ ์•Š์€ ๊ตฌ์—ญ (r, c)์˜ ์„ ๊ฑฐ๊ตฌ ๋ฒˆํ˜ธ๋Š” ๋‹ค์Œ ๊ธฐ์ค€์„ ๋”ฐ๋ฅธ๋‹ค.\n\n
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์•„๋ž˜๋Š” ํฌ๊ธฐ๊ฐ€ 7ร—7์ธ ์žฌํ˜„์‹œ๋ฅผ ๋‹ค์„ฏ ๊ฐœ์˜ ์„ ๊ฑฐ๊ตฌ๋กœ ๋‚˜๋ˆˆ ๋ฐฉ๋ฒ•์˜ ์˜ˆ์‹œ์ด๋‹ค.
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๊ตฌ์—ญ (r, c)์˜ ์ธ๊ตฌ๋Š” A[r][c]์ด๊ณ , ์„ ๊ฑฐ๊ตฌ์˜ ์ธ๊ตฌ๋Š” ์„ ๊ฑฐ๊ตฌ์— ํฌํ•จ๋œ ๊ตฌ์—ญ์˜ ์ธ๊ตฌ๋ฅผ ๋ชจ๋‘ ํ•ฉํ•œ ๊ฐ’์ด๋‹ค. ์„ ๊ฑฐ๊ตฌ๋ฅผ ๋‚˜๋ˆ„๋Š” ๋ฐฉ๋ฒ• ์ค‘์—์„œ, ์ธ๊ตฌ๊ฐ€ ๊ฐ€์žฅ ๋งŽ์€ ์„ ๊ฑฐ๊ตฌ์™€ ๊ฐ€์žฅ ์ ์€ ์„ ๊ฑฐ๊ตฌ์˜ ์ธ๊ตฌ ์ฐจ์ด์˜ ์ตœ์†Ÿ๊ฐ’์„ ๊ตฌํ•ด๋ณด์ž.

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์ž…๋ ฅ

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์ฒซ์งธ ์ค„์— ์žฌํ˜„์‹œ์˜ ํฌ๊ธฐ N์ด ์ฃผ์–ด์ง„๋‹ค.

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๋‘˜์งธ ์ค„๋ถ€ํ„ฐ N๊ฐœ์˜ ์ค„์— N๊ฐœ์˜ ์ •์ˆ˜๊ฐ€ ์ฃผ์–ด์ง„๋‹ค. rํ–‰ c์—ด์˜ ์ •์ˆ˜๋Š” A[r][c]๋ฅผ ์˜๋ฏธํ•œ๋‹ค.

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์ถœ๋ ฅ

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์ฒซ์งธ ์ค„์— ์ธ๊ตฌ๊ฐ€ ๊ฐ€์žฅ ๋งŽ์€ ์„ ๊ฑฐ๊ตฌ์™€ ๊ฐ€์žฅ ์ ์€ ์„ ๊ฑฐ๊ตฌ์˜ ์ธ๊ตฌ ์ฐจ์ด์˜ ์ตœ์†Ÿ๊ฐ’์„ ์ถœ๋ ฅํ•œ๋‹ค.

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๐Ÿ” Algorithm

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์‹œ๋ฎฌ๋ ˆ์ด์…˜, Brute Force

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๐Ÿ’ป Logic

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def divide_area(x, y, d1, d2):\n    sum = [0 for _ in range(5)]\n    isFiveArea = [[False for _ in range(N)]for _ in range(N)]\n\n    # 5๋ฒˆ ์„ ๊ฑฐ๊ตฌ ๊ฒฝ๊ณ„์„  ์ฑ„์šฐ๊ธฐ\n    for i in range(d1+1): isFiveArea[x+i][y-i] = True\n    for i in range(d2+1): isFiveArea[x+i][y+i] = True\n    for i in range(d1+1): isFiveArea[x+d2+i][y+d2-i] = True\n    for i in range(d2+1): isFiveArea[x+d1+i][y-d1+i] = True\n\n    # 5๋ฒˆ ์„ ๊ฑฐ๊ตฌ ๊ฒฝ๊ณ„์„  ์•ˆ์ชฝ ์ฑ„์šฐ๊ธฐ\n    for i in range(x+1, x+d1+d2):\n        check = 0   # 0: default, 1: 5๊ตฌ์—ญ ๊ฒฝ๊ณ„ ์‹œ์ž‘, 2: 5๊ตฌ์—ญ ๊ฒฝ๊ณ„ ๋\n        for j in range(N):\n            if isFiveArea[i][j]: check += 1\n            if check == 1: isFiveArea[i][j] = True\n            elif check == 2: break\n    \n    # ์„ ๊ฑฐ๊ตฌ ์ธ๊ตฌ ๊ณ„์‚ฐ\n    for i in range(N):\n        for j in range(N):\n            if isFiveArea[i][j]:\n                sum[4] += population[i][j]\n            else:\n                if 0 <= j <= y and 0 <= i < x+d1:\n                    sum[0] += population[i][j]\n                elif y < j < N and 0 <= i <= x+d2:\n                    sum[1] += population[i][j]\n                elif 0 <= j < y-d1+d2 and x+d1 <= i < N:\n                    sum[2] += population[i][j]\n                elif y-d1+d2 <= j < N and x+d2 < i < N:\n                    sum[3] += population[i][j]\n    return max(sum) - min(sum)
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result = sys.maxsize\nfor x in range(1, N+1):\n    for y in range(1, N+1):\n        for d1 in range(1, N+1):\n            for d2 in range(1, N+1):\n                if 1 <= x < x+d1+d2 <= N and 1 <= y-d1 < y < y+d2 <= N:\n                    result = min(result, divide_area(x-1, y-1, d1, d2))\nprint(result)
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๐Ÿงฉ Code

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์ „์ฒด ์ฝ”๋“œ ํ™•์ธ\n
import sys\nN = int(sys.stdin.readline())\npopulation = [[int(x) for x in sys.stdin.readline().split()] for _ in range(N)]\n\ndef divide_area(x, y, d1, d2):\n    sum = [0 for _ in range(5)]\n    isFiveArea = [[False for _ in range(N)]for _ in range(N)]\n\n    # 5๋ฒˆ ์„ ๊ฑฐ๊ตฌ ๊ฒฝ๊ณ„์„  ์ฑ„์šฐ๊ธฐ\n    for i in range(d1+1): isFiveArea[x+i][y-i] = True\n    for i in range(d2+1): isFiveArea[x+i][y+i] = True\n    for i in range(d1+1): isFiveArea[x+d2+i][y+d2-i] = True\n    for i in range(d2+1): isFiveArea[x+d1+i][y-d1+i] = True\n\n    # 5๋ฒˆ ์„ ๊ฑฐ๊ตฌ ๊ฒฝ๊ณ„์„  ์•ˆ์ชฝ ์ฑ„์šฐ๊ธฐ\n    for i in range(x+1, x+d1+d2):\n        check = 0   # 0: default, 1: 5๊ตฌ์—ญ ๊ฒฝ๊ณ„ ์‹œ์ž‘, 2: 5๊ตฌ์—ญ ๊ฒฝ๊ณ„ ๋\n        for j in range(N):\n            if isFiveArea[i][j]: check += 1\n            if check == 1: isFiveArea[i][j] = True\n            elif check == 2: break\n    \n    # ์„ ๊ฑฐ๊ตฌ ์ธ๊ตฌ ๊ณ„์‚ฐ\n    for i in range(N):\n        for j in range(N):\n            if isFiveArea[i][j]:\n                sum[4] += population[i][j]\n            else:\n                if 0 <= j <= y and 0 <= i < x+d1:\n                    sum[0] += population[i][j]\n                elif y < j < N and 0 <= i <= x+d2:\n                    sum[1] += population[i][j]\n                elif 0 <= j < y-d1+d2 and x+d1 <= i < N:\n                    sum[2] += population[i][j]\n                elif y-d1+d2 <= j < N and x+d2 < i < N:\n                    sum[3] += population[i][j]\n    return max(sum) - min(sum)\n\nresult = sys.maxsize\nfor x in range(1, N+1):\n    for y in range(1, N+1):\n        for d1 in range(1, N+1):\n            for d2 in range(1, N+1):\n                if 1 <= x < x+d1+d2 <= N and 1 <= y-d1 < y < y+d2 <= N:\n                    result = min(result, divide_area(x-1, y-1, d1, d2))\nprint(result)
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๐Ÿ“ Review

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์ฒ˜์Œ์—๋Š” 5๋ฒˆ ์„ ๊ฑฐ๊ตฌ๊ฐ€ ํŠน์ด ์ผ€์ด์Šค๋ผ๋Š” ๊ฒƒ์„ ๋ชจ๋ฅด๊ณ  1๋ฒˆ ์„ ๊ฑฐ๊ตฌ๋ถ€ํ„ฐ ์ฃผ์–ด์ง„ ์‹์— ๋งž์ถฐ์„œ ๋‚˜๋ˆˆ ๋‹ค์Œ์— ๊ณ„์‚ฐํ•˜๋ ค๊ณ  ํ–ˆ๋‹ค.
\n๊ทธ๋Ÿฌ๋‹ค๊ฐ€ ๋ญ”๊ฐ€ ์ž˜๋ชป๋œ ๊ฒƒ์„ ๊นจ๋‹ซ๊ณ  ๋ฌธ์ œ๋ฅผ ๋‹ค์‹œ ์ฝ์€ ํ›„, ๋ฌธ์ œ์—์„œ ์ œ์‹œ๋œ ์ˆœ์„œ๋Œ€๋กœ ๊ตฌํ˜„ํ•ด๋‚˜๊ฐ”๋‹ค.
\n(r,c)์™€ (x,y) ์ˆœ์„œ์—์„œ ๊ณ„์† ํ—ท๊ฐˆ๋ ค์„œ ํ’€์ด์— ์‹œ๊ฐ„์„ ๋งŽ์ด ์“ด๊ฑด ํ ,,
\n๋‹ค ํ’€๊ณ ๋‚˜๋‹ˆ ์ฝ”๋“œ ๊ณณ๊ณณ์—์„œ ํšจ์œจ์ ์ด์ง€ ์•Š์€ ๋ถ€๋ถ„๋“ค์ด ๋ณด์ด๋Š”๋ฐ ์ด๊ฑด ์ฐจ๊ทผ์ฐจ๊ทผ ๊ณ ์ณ๋‚˜๊ฐ€์•ผ์ง€

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