\n\uc774 \uae00\uc5d0\uc11c\ub294 \uc790\ubc14\ub97c \uc774\uc6a9\ud55c \ucf54\ub529 \ud14c\uc2a4\ud2b8\uc5d0\uc11c \uc790\uc8fc \ucd9c\uc81c\ub418\ub294 “\uc21c\uc5f4\uc758 \uc21c\uc11c \uad6c\ud558\uae30” \ubb38\uc81c\ub97c \ub2e4\ub8e8\uace0\uc790 \ud569\ub2c8\ub2e4. \ud574\ub2f9 \ubb38\uc81c\ub97c \ud574\uacb0\ud558\uae30 \uc704\ud574 \ud544\uc694\ud55c \uc774\ub860, \uc811\uadfc \ubc29\ubc95, \uadf8\ub9ac\uace0 \ucf54\ub4dc \uc608\uc81c\ub97c \uc0c1\uc138\ud788 \uc124\uba85\ud558\uaca0\uc2b5\ub2c8\ub2e4.<\/p>\n<\/header>\n\n\ubb38\uc81c \uc815\uc758<\/h2>\n
\uc8fc\uc5b4\uc9c4 \uc22b\uc790 \ubc30\uc5f4\uc5d0\uc11c, \ud2b9\uc815 \uc22b\uc790\uc758 \uc21c\uc5f4\uc744 \uad6c\ud588\uc744 \ub54c \uadf8 \uc21c\uc5f4\uc774 \uba87 \ubc88\uc9f8\uc5d0 \uc704\uce58\ud558\ub294\uc9c0\ub97c \uad6c\ud558\ub294 \ubb38\uc81c\uc785\ub2c8\ub2e4. \uc608\ub97c \ub4e4\uc5b4, \ubc30\uc5f4\uc774 [1, 2, 3]<\/code>\uc77c \ub54c, \ubaa8\ub4e0 \uc21c\uc5f4\uc744 \ub098\uc5f4\ud558\uba74 \uc544\ub798\uc640 \uac19\uc2b5\ub2c8\ub2e4:<\/p>\n\n- 1, 2, 3<\/li>\n
- 1, 3, 2<\/li>\n
- 2, 1, 3<\/li>\n
- 2, 3, 1<\/li>\n
- 3, 1, 2<\/li>\n
- 3, 2, 1<\/li>\n<\/ul>\n
\uc608\ub97c \ub4e4\uc5b4, \uc22b\uc790 2<\/code>\uc758 \uacbd\uc6b0, \uc21c\uc5f4\uc774 2, 1, 3<\/code>\uc77c \ub54c, \uc774 \uc21c\uc5f4\uc740 3\ubc88\uc9f8\uc5d0 \uc704\uce58\ud558\uac8c \ub429\ub2c8\ub2e4. \uc6b0\ub9ac\ub294 \uc774\ub7ec\ud55c \uc815\ubcf4\ub97c \ubc14\ud0d5\uc73c\ub85c \uc8fc\uc5b4\uc9c4 \uc22b\uc790\uc758 \uc21c\uc5f4\uc774 \uba87 \ubc88\uc9f8\uc778\uc9c0 \uc54c\uc544\ub0bc \uac83\uc785\ub2c8\ub2e4.<\/p>\n<\/section>\n\n\ubb38\uc81c \uc811\uadfc \ubc29\ubc95<\/h2>\n
\uc774 \ubb38\uc81c\ub97c \ud574\uacb0\ud558\uae30 \uc704\ud574 \ub2e4\uc74c\uacfc \uac19\uc740 \ub2e8\uacc4\ub97c \ub530\ub974\uba74 \ub429\ub2c8\ub2e4:<\/p>\n
\n- \uc8fc\uc5b4\uc9c4 \ubc30\uc5f4\uc758 \uae38\uc774\ub97c \ubc14\ud0d5\uc73c\ub85c \ucd1d \uc21c\uc5f4\uc758 \uac1c\uc218\ub97c \uacc4\uc0b0\ud569\ub2c8\ub2e4.<\/li>\n
- \uc8fc\uc5b4\uc9c4 \ud0c0\uac9f \uc21c\uc5f4\uc744 \uae30\uc900\uc73c\ub85c \ud544\uc694\ud55c \uacf5\uc2dd\uc744 \ud1b5\ud574 \uac01 \ub2e8\uacc4\uc5d0\uc11c \uba87 \ubc88\uc9f8\uc778\uc9c0 \uacc4\uc0b0\ud569\ub2c8\ub2e4.<\/li>\n
- \uc21c\uc11c \uacc4\uc0b0\uc744 \uc704\ud55c \uc7ac\uadc0 \ud568\uc218\ub97c \uc791\uc131\ud558\uc5ec \uac01 \ub2e8\uacc4\ubcc4\ub85c \uc21c\uc5f4\uc758 \uc21c\uc11c\ub97c \ucc3e\uc544\ub0c5\ub2c8\ub2e4.<\/li>\n<\/ol>\n<\/section>\n\n
\uc21c\uc5f4\uc758 \uac1c\uc218 \uacc4\uc0b0<\/h2>\n
\uc8fc\uc5b4\uc9c4 \uc22b\uc790 \ubc30\uc5f4\uc758 \uae38\uc774\ub97c n<\/code>\uc774\ub77c\uace0 \ud560 \ub54c, n!<\/code> (n \ud329\ud1a0\ub9ac\uc5bc) \uac1c\uc758 \uc21c\uc5f4\uc774 \uc874\uc7ac\ud569\ub2c8\ub2e4. \uc774\ub294 1\ubd80\ud130 n<\/code>\uae4c\uc9c0\uc758 \ubaa8\ub4e0 \uc815\uc218\ub97c \uacf1\ud55c \uac12\uc785\ub2c8\ub2e4.<\/p>\n\uc608\ub97c \ub4e4\uc5b4, \ubc30\uc5f4\uc758 \uae38\uc774\uac00 3\uc774\ub77c\uba74 \uc21c\uc5f4\uc758 \uac1c\uc218\ub294 3! = 6<\/code>\uc785\ub2c8\ub2e4.<\/p>\n<\/section>\n\n\uc21c\uc11c \uacc4\uc0b0\uc744 \uc704\ud55c \uc74c\uc218\ud654\uc640 \uc7ac\uadc0<\/h2>\n
\uc21c\uc11c\ub97c \uacc4\uc0b0\ud558\uae30 \uc704\ud574\uc11c\ub294 \ud2b9\uc815 \uc22b\uc790\uac00 \uc120\ud0dd\ub41c \uc774\ud6c4\uc758 \uacbd\uc6b0\ub97c \uace0\ub824\ud574\uc57c \ud569\ub2c8\ub2e4. \uc608\ub97c \ub4e4\uc5b4, \uc6b0\ub9ac\uac00 1<\/code>\uc744 \uc120\ud0dd\ud55c\ub2e4\uace0 \uac00\uc815\ud558\uba74, \uadf8 \uc774\ud6c4\ub85c \ub0a8\uc740 \uc22b\uc790\ub4e4\ub85c \uc774\ub8e8\uc5b4\uc9c4 \uc21c\uc5f4\uc758 \uacbd\uc6b0\ub97c \uc7ac\uadc0\uc801\uc73c\ub85c \ud638\ucd9c\ud558\uc5ec \uc21c\uc11c\ub97c \uacc4\uc0b0\ud569\ub2c8\ub2e4.<\/p>\n\uc774\ub7ec\ud55c \uc811\uadfc\ubc95\uc73c\ub85c \uac01 \uc22b\uc790\ubcc4\ub85c \uba87 \uac1c\uc758 \uc21c\uc5f4\uc774 \uac00\ub2a5\ud55c\uc9c0\ub97c \ucc3e\uc544\ub0b4 \uacc4\uc0b0\uc744 \uc218\ud589\ud569\ub2c8\ub2e4.<\/p>\n<\/section>\n\n\uc790\ubc14 \ucf54\ub4dc \uad6c\ud604<\/h2>\n
\uc544\ub798\ub294 “\uc21c\uc5f4\uc758 \uc21c\uc11c \uad6c\ud558\uae30” \ubb38\uc81c\ub97c \ud574\uacb0\ud558\uae30 \uc704\ud55c \uc790\ubc14 \ucf54\ub4dc\uc785\ub2c8\ub2e4:<\/p>\n
\npublic class PermutationOrder {\n \n public static void main(String[] args) {\n int[] numbers = {1, 2, 3}; \/\/ \uc8fc\uc5b4\uc9c4 \ubc30\uc5f4\n int[] target = {2, 1, 3}; \/\/ \uc21c\uc11c \uacc4\uc0b0\ud560 \ud0c0\uac9f \uc21c\uc5f4\n int rank = findRank(numbers, target);\n System.out.println(\"\ud0c0\uac9f \uc21c\uc5f4\uc758 \uc21c\uc11c: \" + rank);\n }\n \n public static int findRank(int[] numbers, int[] target) {\n int n = numbers.length;\n boolean[] used = new boolean[n];\n return getRank(numbers, target, used, 0);\n }\n \n private static int getRank(int[] numbers, int[] target, boolean[] used, int index) {\n int rank = 1; \/\/ \uae30\ubcf8 \uc21c\uc11c\ub294 1\ubd80\ud130 \uc2dc\uc791\n int n = numbers.length;\n \n for (int i = 0; i < n; i++) {\n \/\/ \ud0c0\uac9f \uc22b\uc790\ubcf4\ub2e4 \uc791\uc740 \uacbd\uc6b0\n if (!used[i]) {\n for (int j = 0; j < target[index]; j++) {\n if (j == numbers[i]) {\n break;\n }\n rank += factorial(n - index - 1); \/\/ (n-1)! \ub9cc\ud07c \ucd94\uac00\n }\n }\n if (target[index] == numbers[i]) {\n used[i] = true; \/\/ \ud574\ub2f9 \uc22b\uc790\ub97c \uc0ac\uc6a9\ud568\n break;\n }\n }\n \n if (index < n - 1) {\n rank += getRank(numbers, target, used, index + 1); \/\/ \ub2e4\uc74c \uc778\ub371\uc2a4\ub97c \uc704\ud574 \uc7ac\uadc0 \ud638\ucd9c\n }\n \n return rank;\n }\n\n private static int factorial(int n) {\n if (n == 0) return 1;\n int result = 1;\n for (int i = 1; i <= n; i++) {\n result *= i;\n }\n return result;\n }\n}\n <\/code><\/pre>\n\uc774 \ucf54\ub4dc\uc5d0\uc11c\ub294 \uc8fc\uc5b4\uc9c4 \uc22b\uc790 \ubc30\uc5f4\uacfc \ubaa9\ud45c \uc21c\uc5f4\uc744 \uae30\ubc18\uc73c\ub85c \uc21c\uc11c\ub97c \uacc4\uc0b0\ud558\uae30 \uc704\ud574 \uc7ac\uadc0\uc801 \uc811\uadfc\ubc95\uc744 \uc0ac\uc6a9\ud569\ub2c8\ub2e4. \uc8fc\uc694 \ud568\uc218 getRank<\/code>\ub294 \uc810\uc9c4\uc801\uc73c\ub85c \ud0c0\uac9f \uc21c\uc5f4\uc5d0\uc11c \uac01 \uc22b\uc790\ub97c \uac80\uc0ac\ud558\uace0, \ub2e4\ub978 \uc22b\uc790\ub4e4\uacfc\uc758 \uc870\ud569\uc5d0 \ub530\ub77c \uc21c\uc11c\ub97c \uacb0\uc815\ud569\ub2c8\ub2e4.<\/p>\n<\/section>\n\n\uc608\uc81c \ud14c\uc2a4\ud2b8 \ucf00\uc774\uc2a4<\/h2>\n
\ucf54\ub4dc\ub97c \uc791\uc131\ud55c \ud6c4 \ub2e4\uc74c\uacfc \uac19\uc740 \uc5ec\ub7ec \uc608\uc81c\ub97c \ud1b5\ud574 \uacb0\uacfc\ub97c \uac80\uc99d\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4:<\/p>\n
\n- \uc785\ub825:
[1, 2, 3]<\/code>, \ud0c0\uac9f: [2, 1, 3]<\/code> \u2192 \ucd9c\ub825: 3<\/li>\n- \uc785\ub825:
[1, 2, 3]<\/code>, \ud0c0\uac9f: [1, 3, 2]<\/code> \u2192 \ucd9c\ub825: 2<\/li>\n- \uc785\ub825:
[1, 2, 3]<\/code>, \ud0c0\uac9f: [3, 2, 1]<\/code> \u2192 \ucd9c\ub825: 6<\/li>\n<\/ul>\n\uc704\uc758 \ucf54\ub4dc\ub85c \ub2e4\uc591\ud55c \ubc30\uc5f4\uacfc \ud0c0\uac9f \uc21c\uc5f4\uc744 \uc2e4\ud5d8\ud558\uc5ec \uc62c\ubc14\ub978 \ucd9c\ub825\uc744 \uc5bb\uae30\uae4c\uc9c0 \uc5bc\ub9c8\ub4e0\uc9c0 \ubc18\ubcf5\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4. \uc21c\uc5f4\uc758 \uc870\ud569\ub9cc\uc73c\ub85c\ub3c4 \ub2e4\uc591\ud55c \ud14c\uc2a4\ud2b8 \ucf00\uc774\uc2a4\uac00 \uc0dd\uc131 \uac00\ub2a5\ud558\ubbc0\ub85c, \uc54c\uace0\ub9ac\uc998\uc758 \uc815\ud655\uc131\uacfc \ud6a8\uc728\uc131\uc744 \ub530\uc838\ubd10\uc57c \ud569\ub2c8\ub2e4.<\/p>\n<\/section>\n\n\uacb0\ub860<\/h2>\n
\uc774\ubc88 \uae00\uc5d0\uc11c\ub294 \uc790\ubc14\ub97c \ud65c\uc6a9\ud558\uc5ec \uc21c\uc5f4\uc758 \uc21c\uc11c\ub97c \uad6c\ud558\ub294 \ubb38\uc81c\ub97c \ub2e4\ub8e8\uc5b4 \ubcf4\uc558\uc2b5\ub2c8\ub2e4. \uc7ac\uadc0\uc801\uc778 \uc811\uadfc \ubc29\uc2dd\uacfc \uc21c\uc5f4\uc758 \uac1c\uc218 \uacc4\uc0b0, \uadf8\ub9ac\uace0 \uc815\ud655\ud55c \uc21c\uc11c \ud655\uc778\uc744 \uc704\ud55c \uc54c\uace0\ub9ac\uc998\uc774 \uacb0\ud569\ud574 \ubb38\uc81c\ub97c \ud6a8\uacfc\uc801\uc73c\ub85c \ud574\uacb0\ud560 \uc218 \uc788\uc5c8\ub358 \uc810\uc744 \uac15\uc870\ud558\uace0 \uc2f6\uc2b5\ub2c8\ub2e4. \uc774\ub97c \ud1b5\ud574 \ucf54\ub529 \ud14c\uc2a4\ud2b8\uc5d0 \ub300\ud55c \uc774\ud574\ub3c4\uac00 \ub192\uc544\uc9c0\uace0 \ubcf4\ub2e4 \ub2e4\uc591\ud55c \ubb38\uc81c\ub97c \ud574\uacb0\ud558\ub294 \ub370 \ud070 \ub3c4\uc6c0\uc774 \ub418\uae38 \ubc14\ub78d\ub2c8\ub2e4.<\/p>\n<\/section>\n