銆岀畻娉曚笌鏁版嵁缁撴瀯銆嶅甫浣犵湅鍝堝笇绠楁硶涔嬬編

Posted 2021-04-12 鍓嶇UpUp

鍓嶈█

鏈€杩戝湪鏌愰潰缁忎笂锛岀湅鍒板叧浜庡搱甯岃〃鐩稿叧鐨勯棶棰橈紝瀵硅繖涓暟鎹粨鏋勬劅鍏磋叮锛屼簬鏄氨鏈変簡杩欑瘒鏂囩珷銆?/p>

濡傛灉浣犵粡甯稿惉鍒?code class="mq-6">鍝堝笇绠楁硶锛?code class="mq-7">鍝堝笇琛?/code>锛?code class="mq-8">鍝堝笇鍐茬獊,浣嗗張鏄湁鐐规ā妫变袱鍙殑姒傚康锛岃涓嶅畾璇诲畬鏈枃锛屽浣犱簺璁告湁鐐瑰府鍔┿€?/p>

鑱旂郴馃憠TianTianUp锛岄亣鍒伴棶棰樼殑璇濓紝鍙互鑱旂郴浣滆€呭櫌锛屾効鎰忛櫔浣犱竴璧峰涔犱竴璧锋帰璁ㄩ棶棰樸€?/p>

鑴戝浘馃憞

鍝堝笇琛?

涓昏鍥寸粫杩欏嚑涓柟闈粙缁嶐煈?/p>

• 鍝堝笇姒傚康浠嬬粛
• 鍝堝笇鍑芥暟
• 鍝堝笇琛?
• 濡備綍瑙ｅ喅鍝堝笇鍐茬獊
• 鍝堝笇搴旂敤
• leetcode鍝堝笇琛ㄥ疄璺?

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鍩烘湰浠嬬粛

鍙兘浣犲惉杩囨暎鍒楄〃锛屾暎鍒楀嚱鏁帮紝瀹冧滑璺熷搱甯岃〃锛屽搱甯屽嚱鏁版槸涓€涓蹇碉紝鎺ヤ笅鏉ユ垜灏变互鍝堝笇杩欎袱涓叧閿瓧鏉ユ⒊鐞嗐€?/p>

鍝堝笇鍩烘湰姒傚康1

鍝堝笇姒傚康

鍊熺敤涓€娈佃瘽鏉ユ弿杩板搱甯岀殑姒傚康馃憞

鏁ｅ垪锛坔ashing锛夋槸鐢佃剳绉戝涓竴绉嶅璧勬枡鐨勫鐞嗘柟娉曪紝閫氳繃鏌愮鐗瑰畾鐨勫嚱鏁?绠楁硶锛堢О涓烘暎鍒楀嚱鏁?绠楁硶锛夊皢瑕佹绱㈢殑椤逛笌鐢ㄦ潵妫€绱㈢殑绱㈠紩锛堢О涓烘暎鍒楋紝鎴栬€呮暎鍒楀€硷級鍏宠仈璧锋潵锛岀敓鎴愪竴绉嶄究浜庢悳绱㈢殑鏁版嵁缁撴瀯锛堢О涓烘暎鍒楄〃锛夈€備篃璇戜负鏁ｅ垪銆傛棫璇戝搱甯岋紙璇互涓烘槸浜哄悕鑰岄噰鐢ㄤ簡闊宠瘧锛夈€傚畠涔熷父鐢ㄤ綔涓€绉嶈祫璁畨鍏ㄧ殑瀹炰綔鏂规硶锛岀敱涓€涓茶祫鏂欎腑缁忚繃鏁ｅ垪绠楁硶锛圚ashing algorithms锛夎绠楀嚭鏉ョ殑璧勬枡鎸囩汗锛坉ata fingerprint锛夛紝缁忓父鐢ㄦ潵璇嗗埆妗ｆ涓庤祫鏂欐槸鍚︽湁琚獪鏀癸紝浠ヤ繚璇佹。妗堜笌璧勬枡纭疄鏄敱鍘熷垱鑰呮墍鎻愪緵銆?nbsp;    ----Wikipedia

鎬荤粨鐨勮瘽锛屾垜鐨勭悊瑙ｅ氨鏄皢浠绘剰鏁伴噺鐨勬暟鎹€氳繃鍝堝笇绠楁硶寰楀埌涓€涓浐瀹氱殑缁撴灉锛岃繖鏍峰瓙鎴戜滑鏌ユ壘鏌愪釜閿殑璇濓紝閫熷害涔熷ぇ澶ф彁鍗囷紝褰撶劧浜嗭紝杈撳叆鏁版嵁鍙戠敓鏀瑰彉鐨勮瘽锛屽垯鍝堝笇涔熶細鍙戠幇鏀瑰彉銆?/p>

鍝堝笇鍑芥暟

甯歌鐨刪ash绠楁硶馃憞

1. 銆孧D4銆?/strong>

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2. 銆孧D5銆?/strong>

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3. 銆孲HA-1鍙婂叾浠栥€?/strong>

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鍝堝笇琛?/span>

浠€涔堟槸鍝堝笇琛紝澶ф璇寸殑鎰忔€濆氨鏄?Hash table锛屼篃鍙暎鍒楄〃)锛屽畠鏄€氳繃hash绠楁硶寰楁潵鐨勶紝閫氬父鑰岃█锛屾槸涓€涓浐瀹氶暱搴︾殑鏁扮粍銆?/p>

鍋囪鍏抽敭瀛椾负value,閭ｄ箞鍏跺€煎瓨鍦ㄤ笌hash(value)鐨勫瓨鍌ㄤ綅缃笂锛屼笉闇€瑕佹瘮杈冨氨鍙互鐩存帴鎷垮埌鎵€鏌ヨ褰曪紝绉拌繖涓搴斿叧绯籪涓烘暎鍒楀嚱鏁帮紝鎸夎繖涓€濇兂寤虹珛鐨勮〃涓烘暎鍒楄〃銆?/p>

鎬荤殑鏉ヨ锛屽搱甯岃〃灏辨槸涓€绉嶆槧灏勫叧绯荤殑琛紝浣犲彲浠ユ牴鎹繖涓槧灏勫叧绯荤敱閿紙鍏抽敭瀛楋級鎵惧埌鍊笺€?/p>

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濡備綍瑙ｅ喅鍝堝笇鍐茬獊

鍝堝笇鍩烘湰姒傚康2

棣栧厛鎴戜滑鐨勬竻妤氬暐鏄搱甯屽啿绐侌煈?/p>

鐢变簬鍝堝笇绠楁硶琚绠楃殑鏁版嵁鏄棤闄愮殑锛岃€岃绠楀悗鐨勭粨鏋滆寖鍥存湁闄愶紝鍥犳鎬讳細瀛樺湪涓嶅悓鐨勬暟鎹粡杩囪绠楀悗寰楀埌鐨勫€肩浉鍚岋紝杩欏氨鏄搱甯屽啿绐併€?/p>

瑙ｅ喅鏂规硶鏈夊摢浜涘憿馃憞

• 閾惧湴鍧€娉?
• 寮€鏀惧湴鍧€娉?

鍝堝笇鍐茬獊-閾惧湴鍧€娉?

浠庤繖寮犲浘涓婃潵鐪嬬殑璇濓紝灏卞緢濂界悊瑙ｅ畠鐨勮繖绉嶆€濊矾浜嗭紝涓€鑸€岃█锛岄摼琛ㄧ殑闀垮害涔熸槸瑙勫畾鏈€闀夸负8锛屽叿浣撲负浠€涔堬紝鏈夊叴瓒ｇ殑灏忎紮浼村彲浠ュ幓娣卞叆浜嗚В銆?/p>

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杩欑鎬濊矾瑙ｅ喅鍐茬獊鐨勬€濊矾馃憠銆屽鎵剧┖鐧界殑鍗曞厓鏍兼潵娣诲姞閲嶅鐨勬暟鎹€?/strong>

閭ｄ箞杩欑鏂规硶鏈夊叿浣撶殑鎺㈡祴涓夌鏂规硶馃憞

• 绾挎€ц瘯鎺㈡硶
• 浜屾鎺㈡祴
• 鍐嶅搱甯屾硶

銆岀嚎鎬ф帰娴嬫硶銆?/strong>

銆屼簩娆℃帰娴嬨€?/strong>

銆屽啀鍝堝笇娉曘€?/strong>

鎶婂叧閿瓧鐢ㄥ彟澶栦竴涓搱甯屽嚱鏁帮紝鍐嶅仛涓€娆″搱甯屽寲锛岀敤杩欐鍝堝笇鍖栫殑缁撴灉浣滀负姝ラ暱銆?/p>

銆屽缓绔嬪叕鍏辨孩鍑哄尯銆?/strong>

灏嗗搱甯岃〃鍒嗕负鍩烘湰琛ㄥ拰婧㈠嚭琛ㄤ袱閮ㄥ垎锛屽嚒鏄拰鍩烘湰琛ㄥ彂鐢熷啿绐佺殑鍏冪礌锛屼竴寰嬪～鍏ユ孩鍑鸿〃(娉ㄦ剰锛氬湪杩欎釜鏂规硶閲岄潰鏄妸鍏冪礌鍒嗗紑涓や釜琛ㄦ潵瀛樺偍)銆?/p>

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鍝堝笇搴旂敤

鍝堝笇绠楁硶鏈夊摢浜涘簲鐢ㄥ満鏅憿锛岃繖閲屾⒊鐞嗗嚑涓煈?/p>

銆屽畨鍏ㄥ姞瀵嗐€?/strong>

鏃ュ父鐢ㄦ埛瀵嗙爜鍔犲瘑閫氬父浣跨敤鐨勯兘鏄?md5銆乻ha绛夊搱甯屽嚱鏁帮紝鍥犱负涓嶅彲閫嗭紝鑰屼笖寰皬鐨勫尯鍒姞瀵嗕箣鍚庣殑缁撴灉宸窛寰堝ぇ锛屾墍浠ュ畨鍏ㄦ€ф洿濂姐€?/p>

銆屽敮涓€鏍囪瘑銆?/strong>

姣斿 URL 瀛楁鎴栬€呭浘鐗囧瓧娈佃姹備笉鑳介噸澶嶏紝杩欎釜鏃跺€欏氨鍙互閫氳繃瀵圭浉搴斿瓧娈靛€煎仛 md5 澶勭悊锛屽皢鏁版嵁缁熶竴涓?32 浣嶉暱搴︿粠鏁版嵁搴撶储寮曟瀯寤哄拰鏌ヨ瑙掑害鏁堟灉鏇村ソ锛屾澶栵紝杩樺彲浠ュ鏂囦欢涔嬬被鐨勪簩杩涘埗鏁版嵁鍋?md5 澶勭悊锛屼綔涓哄敮涓€鏍囪瘑锛岃繖鏍峰垽瀹氶噸澶嶆枃浠剁殑鏃跺€欐洿蹇嵎銆?/p>

銆屾暟鎹牎楠屻€?/strong>

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3涓緥瀛?/span>

瀵瑰搱甯岃〃鏁版嵁缁撴瀯鏈変簡涓€瀹氱殑璁よ瘑鍚庯紝鎺ヤ笅鏉ワ紝閫氳繃涓€瀹氱殑棰橀噺鏉ョ粌涔狅紝涓嬪崍鍑嗗浜?閬搇eetcode棰樼洰鍏充簬鍝堝笇琛ㄧ殑锛岄毦搴︿粠绠€鍗曞埌鍥伴毦馃憞

• 涓ゆ暟涔嬪拰猸?
• 鏈夋晥鐨勫瓧姣嶅紓浣嶈瘝猸?
• 鏃犻噸澶嶅瓧绗︾殑鏈€闀垮瓙涓测瓙猸?
• 鍓岾涓珮棰戝崟璇嶁瓙猸?
• 鍘熷瓙鐨勬暟閲忊瓙猸愨瓙

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鎺ヤ笅鏉ワ紝鎴戜滑灏变互涓夐涓轰緥瀛愶紝鏉ョ湅鐪嬪搱甯岃〃鍦ㄩ鐩腑璇ヨ繖涔堝簲鐢煈?/p>

涓ゆ暟涔嬪拰猸?/span>

閾炬帴锛氫袱鏁颁箣鍜?/p>

缁欏畾涓€涓暣鏁版暟缁?nums 鍜屼竴涓洰鏍囧€?target锛岃浣犲湪璇ユ暟缁勪腑鎵惧嚭鍜屼负鐩爣鍊肩殑閭?涓や釜 鏁存暟锛屽苟杩斿洖浠栦滑鐨勬暟缁勪笅鏍囥€?/p>

浣犲彲浠ュ亣璁炬瘡绉嶈緭鍏ュ彧浼氬搴斾竴涓瓟妗堛€備絾鏄紝鏁扮粍涓悓涓€涓厓绱犱笉鑳戒娇鐢ㄤ袱閬嶃€?/p>

绀轰緥:

缁欏畾 nums = [2, 7, 11, 15], target = 9

鍥犱负 nums[0] + nums[1] = 2 + 7 = 9 鎵€浠ヨ繑鍥?[0, 1]

鏉ユ簮锛氬姏鎵ｏ紙LeetCode锛?閾炬帴锛歨ttps://leetcode-cn.com/problems/two-sum 钁椾綔鏉冨綊棰嗘墸缃戠粶鎵€鏈夈€傚晢涓氳浆杞借鑱旂郴瀹樻柟鎺堟潈锛岄潪鍟嗕笟杞浇璇锋敞鏄庡嚭澶勩€?/p>

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杩欓鏈€绠€鍗曞仛娉曞氨鏄疧(n*n)澶嶆潅搴︼紝鍦ㄨ繖閲岋紝鎴戜滑鏈夎€冭檻浣跨敤Map鏉ラ檷浣庢椂闂村鏉傚害锛岄鐩姹傜瓟妗堣繑鍥炵殑鏄笅鏍囷紝鎵€浠ユ垜浠琈ap鍙互鍋氫竴涓槧灏勶紝灏嗗綋鍓嶇殑鍊硷紝涓庝笅鏍噄ndex鍋氭槧灏勩€?/p>

鍝堝笇琛?棰樼洰1

浠ｇ爜鐐硅繖閲屸槕锔?/p>

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鏃犻噸澶嶅瓧绗︾殑鏈€闀垮瓙涓测瓙猸?/span>

閾炬帴锛氭棤閲嶅瀛楃鐨勬渶闀垮瓙涓?/p>

缁欏畾涓€涓瓧绗︿覆锛岃浣犳壘鍑哄叾涓笉鍚湁閲嶅瀛楃鐨?鏈€闀垮瓙涓?鐨勯暱搴︺€?/p>

绀轰緥 1:

杈撳叆: "abcabcbb" 杈撳嚭: 3 

瑙ｉ噴: 鍥犱负鏃犻噸澶嶅瓧绗︾殑鏈€闀垮瓙涓叉槸 "abc"锛屾墍浠ュ叾闀垮害涓?3銆?/p>

绀轰緥 2:

杈撳叆: "bbbbb" 杈撳嚭: 1 

瑙ｉ噴: 鍥犱负鏃犻噸澶嶅瓧绗︾殑鏈€闀垮瓙涓叉槸 "b"锛屾墍浠ュ叾闀垮害涓?1銆?/p>

绀轰緥 3:

杈撳叆: "pwwkew" 杈撳嚭: 3

瑙ｉ噴: 鍥犱负鏃犻噸澶嶅瓧绗︾殑鏈€闀垮瓙涓叉槸 "wke"锛屾墍浠ュ叾闀垮害涓?3銆?/p>

璇锋敞鎰忥紝浣犵殑绛旀蹇呴』鏄?瀛愪覆 鐨勯暱搴︼紝"pwke" 鏄竴涓瓙搴忓垪锛屼笉鏄瓙涓层€?/p>

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鏆村姏瑙ｆ硶鏃堕棿澶嶆潅搴﹁緝楂橈紝浼氳揪鍒?O(n^2)锛岄偅涔堝浣曟潵闄嶄綆鏃堕棿澶嶆潅搴﹀憿馃憞

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• end鎸囬拡涓嶆柇鍚戝悗璧帮紝褰撻亣鍒板尯闂碵start,end]鐩稿悓鐨勫瓧绗︽椂锛屾垜浠氨闇€瑕侀噸鏂拌窡鏂皊tart鎸囬拡锛屽苟涓旀妸姝ゆ椂鐨勭瓟妗坅ns鏇存柊鍗冲彲銆?

浠ｇ爜馃憞

鍝堝笇琛?棰樼洰2

浠ｇ爜鐐硅繖閲屸槕锔?/p>

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鍓岾涓珮棰戝崟璇嶁瓙猸?/span>

閾炬帴锛氬墠K涓珮棰戝崟璇?/p>

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绀轰緥 1锛?/p>

杈撳叆: ["i", "love", "leetcode", "i", "love", "coding"], k = 2 

杈撳嚭: ["i", "love"] 

瑙ｆ瀽: "i" 鍜?"love" 涓哄嚭鐜版鏁版渶澶氱殑涓や釜鍗曡瘝锛屽潎涓?娆°€?/p>

娉ㄦ剰锛屾寜瀛楁瘝椤哄簭 "i" 鍦?"love" 涔嬪墠銆?/p>

绀轰緥 2锛?/p>

杈撳叆: ["the", "day", "is", "sunny", "the", "the", "the", "sunny", "is", "is"], k = 4 

杈撳嚭: ["the", "is", "sunny", "day"] 

瑙ｆ瀽: "the", "is", "sunny" 鍜?"day" 

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娉ㄦ剰锛?/p>

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鏉ユ簮锛氬姏鎵ｏ紙LeetCode锛?閾炬帴锛歨ttps://leetcode-cn.com/problems/top-k-frequent-words 钁椾綔鏉冨綊棰嗘墸缃戠粶鎵€鏈夈€傚晢涓氳浆杞借鑱旂郴瀹樻柟鎺堟潈锛岄潪鍟嗕笟杞浇璇锋敞鏄庡嚭澶勩€?/p>

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• 闇€瑕佹眰鐨勫墠k涓嚭鐜版鏁版渶澶氱殑锛岄偅涔堟垜浠彧闇€瑕佺粺璁℃鏁?
• map鏁版嵁缁撴瀯缁存姢锛坰tr,count锛夛紝str琛ㄧず鐨勬槸瀵逛簬鐨勫瓧绗︿覆锛宑ount琛ㄧず鐨勬槸鍑虹幇娆℃暟
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鍝堝笇琛?棰樼洰3

浠ｇ爜鐐硅繖閲屸槕锔?/p>

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2. 鍏虫敞鍏紬鍙?/span> 銆屽墠绔疷pUp銆?/strong> 锛岃仈绯讳綔鑰咃紝鎴戜滑涓€璧峰涔犱竴璧疯繘姝ャ€?/span>
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