\uc774 \uac15\uc88c\uc5d0\uc11c\ub294 \uc790\ubc14\uc2a4\ud06c\ub9bd\ud2b8 \ucf54\ub529\ud14c\uc2a4\ud2b8 \ubb38\uc81c\ub97c \ud574\uacb0\ud558\ub294 \ubc29\ubc95\uc744 \ub2e4\ub8e8\uace0\uc790 \ud569\ub2c8\ub2e4. \ubb38\uc81c\uc758 \uc8fc\uc81c\ub294 \uc18c\uc218<\/strong>\uc640 \ud330\ub9b0\ub4dc\ub86c \uc218<\/strong> \uc911\uc5d0\uc11c \ucd5c\uc19f\uac12\uc744 \ucc3e\ub294 \uac83\uc785\ub2c8\ub2e4. \uc774 \ubb38\uc81c\ub97c \ud574\uacb0\ud558\uae30 \uc704\ud574 \ud544\uc694\ud55c \uc54c\uace0\ub9ac\uc998\uacfc \ud568\uaed8, \ubb38\uc81c\ud574\uacb0 \uacfc\uc815\uc744 \ub2e8\uacc4\ubcc4\ub85c \uc548\ub0b4\ud560 \uac83\uc785\ub2c8\ub2e4.<\/p>\n \uc8fc\uc5b4\uc9c4 \uc815\uc218 N\uc774 \uc788\uc2b5\ub2c8\ub2e4. 1\ubd80\ud130 N\uae4c\uc9c0\uc758 \ubaa8\ub4e0 \uc22b\uc790 \uc911\uc5d0\uc11c \uc18c\uc218\uc774\uba74\uc11c \ud330\ub9b0\ub4dc\ub86c\uc778 \uc218\ub4e4 \uc911\uc5d0\uc11c \ucd5c\uc19f\uac12\uc744 \ucc3e\uc544\uc57c \ud569\ub2c8\ub2e4. \ub9cc\uc57d \uadf8\ub7f0 \uc218\uac00 \uc874\uc7ac\ud558\uc9c0 \uc54a\uc73c\uba74 -1\uc744 \ubc18\ud658\ud569\ub2c8\ub2e4.<\/p>\n \ubb38\uc81c\ub97c \ud574\uacb0\ud558\uae30 \uc704\ud574 \ub2e4\uc74c\uacfc \uac19\uc740 \ubc29\ubc95\uc744 \uc0ac\uc6a9\ud560 \uac83\uc785\ub2c8\ub2e4.<\/p>\n \uc18c\uc218\ub97c \ucc3e\uae30 \uc704\ud574\uc5d4 \uac04\ub2e8\ud55c \uc5d0\ub77c\ud1a0\uc2a4\ud14c\ub124\uc2a4\uc758 \uccb4(Sieve of Eratosthenes) \uc54c\uace0\ub9ac\uc998\uc744 \uc0ac\uc6a9\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4. \uc774 \uc54c\uace0\ub9ac\uc998\uc740 O(n log log n)\uc758 \uc2dc\uac04 \ubcf5\uc7a1\ub3c4\ub85c \uc18c\uc218\ub97c \ucc3e\uc744 \uc218 \uc788\ub294 \ud6a8\uc728\uc801\uc778 \ubc29\ubc95\uc785\ub2c8\ub2e4.<\/p>\n \ud330\ub9b0\ub4dc\ub86c \uc218\ub294 \uc815\uc218 \ud615\ud0dc\uc758 \uc22b\uc790\uac00 \uc815\ubc29\ud5a5\uacfc \uc5ed\ubc29\ud5a5\uc774 \ub3d9\uc77c\ud55c \uc218\ub97c \uc758\ubbf8\ud569\ub2c8\ub2e4. \uc608\ub97c \ub4e4\uc5b4, 121, 1331 \ub4f1\uc785\ub2c8\ub2e4.<\/p>\n \uc774\uc81c \uc18c\uc218\uc774\uba74\uc11c \ud330\ub9b0\ub4dc\ub86c\uc778 \uc218\ub4e4\uc744 \ubaa8\uc544 \ucd5c\uc19f\uac12\uc744 \ucc3e\uc73c\uba74 \ub429\ub2c8\ub2e4.<\/p>\n \uc774\uc81c \ubaa8\ub4e0 \ub2e8\uacc4\ub97c \uacb0\ud569\ud55c \ucd5c\uc885 \ucf54\ub4dc\ub97c \ud655\uc778\ud574\ubcf4\uaca0\uc2b5\ub2c8\ub2e4.<\/p>\n \uc774\ubc88 \uac15\uc88c\uc5d0\uc11c\ub294 \uc18c\uc218\uc640 \ud330\ub9b0\ub4dc\ub86c \uc218 \uc911\uc5d0\uc11c \ucd5c\uc19f\uac12\uc744 \ucc3e\ub294 \ubb38\uc81c\ub97c \ud574\uacb0\ud558\uae30 \uc704\ud55c \uc54c\uace0\ub9ac\uc998\uc744 \uad6c\ud604\ud574\ubcf4\uc558\uc2b5\ub2c8\ub2e4. \uc5d0\ub77c\ud1a0\uc2a4\ud14c\ub124\uc2a4\uc758 \uccb4\ub97c \uc0ac\uc6a9\ud558\uc5ec \ud6a8\uc728\uc801\uc73c\ub85c \uc18c\uc218\ub97c \ucc3e\uace0, \ud330\ub9b0\ub4dc\ub86c \uc218\ub97c \ud655\uc778\ud558\uba70, \ucd5c\uc885\uc801\uc73c\ub85c \uc870\uac74\uc5d0 \ub9de\ub294 \ucd5c\uc19f\uac12\uc744 \ucc3e\uc544\ub0b4\ub294 \uacfc\uc815\uc744 \uc0b4\ud3b4\ubcf4\uc558\uc2b5\ub2c8\ub2e4. \uc774\ub7f0 \ubb38\uc81c\ub97c \ud480\uae30 \uc704\ud574\uc11c\ub294 \uc54c\uace0\ub9ac\uc998\uc801 \uc0ac\uace0\uc640 \ud568\uaed8 \ud504\ub85c\uadf8\ub798\ubc0d \ub2a5\ub825 \ub610\ud55c \ud544\uc694\ud569\ub2c8\ub2e4. \uc55e\uc73c\ub85c\ub3c4 \ub2e4\uc591\ud55c \ucf54\ub529 \ubb38\uc81c\ub97c \ud1b5\ud574 \uc2e4\ub825\uc744 \ub2e4\uc838\ub098\uac00\uae38 \ubc14\ub78d\ub2c8\ub2e4.<\/p>\n <\/body><\/p>\n","protected":false},"excerpt":{"rendered":"\ubb38\uc81c \uc815\uc758<\/h2>\n
\ubb38\uc81c \uc608\uc2dc<\/h3>\n
\n
\ucd9c\ub825: 3 (\uc18c\uc218: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31 \uc911\uc5d0\uc11c \ud330\ub9b0\ub4dc\ub86c\uc778 \uc218\ub294 3)<\/li>\n
\ucd9c\ub825: 11 (\uc18c\uc218\uc778 11\uc740 \ud330\ub9b0\ub4dc\ub86c \uc218)<\/li>\n
\ucd9c\ub825: -1 (1\uc740 \uc18c\uc218\ub3c4, \ud330\ub9b0\ub4dc\ub86c \uc218\ub3c4 \uc544\ub2d8)<\/li>\n<\/ul>\n\ubb38\uc81c \ud574\uacb0 \uc811\uadfc\ubc95<\/h2>\n
\n
\ub2e8\uacc4\ubcc4 \uad6c\ud604<\/h2>\n
1\ub2e8\uacc4: \uc18c\uc218 \ucc3e\uae30<\/h3>\n
function findPrimes(n) {\n const isPrime = Array(n + 1).fill(true);\n isPrime[0] = isPrime[1] = false; \/\/ 0\uacfc 1\uc740 \uc18c\uc218\uac00 \uc544\ub2d9\ub2c8\ub2e4.\n \n for (let i = 2; i * i <= n; i++) {\n if (isPrime[i]) {\n for (let j = i * i; j <= n; j += i) {\n isPrime[j] = false; \/\/ i\uc758 \ubc30\uc218\ub97c \uc18c\uc218\uc5d0\uc11c \uc81c\uc678\n }\n }\n }\n \n const primes = [];\n for (let i = 2; i <= n; i++) {\n if (isPrime[i]) {\n primes.push(i);\n }\n }\n return primes;\n }<\/code><\/pre>\n2\ub2e8\uacc4: \ud330\ub9b0\ub4dc\ub86c \uc218 \ucc3e\uae30<\/h3>\n
function isPalindrome(num) {\n const str = num.toString();\n return str === str.split('').reverse().join('');\n }<\/code><\/pre>\n3\ub2e8\uacc4: \ucd5c\uc19f\uac12 \ucc3e\uae30<\/h3>\n
function findMinPalindromicPrime(n) {\n const primes = findPrimes(n);\n const palindromicPrimes = primes.filter(isPalindrome);\n \n return palindromicPrimes.length > 0 ? Math.min(...palindromicPrimes) : -1;\n }<\/code><\/pre>\n\uc804\uccb4 \ucf54\ub4dc<\/h2>\n
function isPalindrome(num) {\n const str = num.toString();\n return str === str.split('').reverse().join('');\n }\n\n function findPrimes(n) {\n const isPrime = Array(n + 1).fill(true);\n isPrime[0] = isPrime[1] = false;\n\n for (let i = 2; i * i <= n; i++) {\n if (isPrime[i]) {\n for (let j = i * i; j <= n; j += i) {\n isPrime[j] = false;\n }\n }\n }\n\n const primes = [];\n for (let i = 2; i <= n; i++) {\n if (isPrime[i]) {\n primes.push(i);\n }\n }\n return primes;\n }\n\n function findMinPalindromicPrime(n) {\n const primes = findPrimes(n);\n const palindromicPrimes = primes.filter(isPalindrome);\n \n return palindromicPrimes.length > 0 ? Math.min(...palindromicPrimes) : -1;\n }\n\n \/\/ \uc0ac\uc6a9 \uc608\uc2dc\n console.log(findMinPalindromicPrime(31)); \/\/ \ucd9c\ub825: 3\n console.log(findMinPalindromicPrime(11)); \/\/ \ucd9c\ub825: 11\n console.log(findMinPalindromicPrime(1)); \/\/ \ucd9c\ub825: -1<\/code><\/pre>\n\uacb0\ub860<\/h2>\n