{"id":208293,"date":"2025-07-08T12:27:23","date_gmt":"2025-07-08T04:27:23","guid":{"rendered":"https:\/\/server.hk\/cnblog\/208293\/"},"modified":"2025-07-08T12:27:23","modified_gmt":"2025-07-08T04:27:23","slug":"%e5%a6%82%e4%bd%95%e5%9c%a8golang%e4%b8%ad%e6%89%8b%e5%8a%a8%e9%87%8a%e6%94%be%e5%86%85%e5%ad%98","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/208293\/","title":{"rendered":"\u5982\u4f55\u5728golang\u4e2d\u624b\u52a8\u91ca\u653e\u5185\u5b58"},"content":{"rendered":"

<\/b> <\/p>\n

\u5f53\u524d\u4f4d\u7f6e\uff1a ><\/span> ><\/span> ><\/span> ><\/span> \u5982\u4f55\u5728golang\u4e2d\u624b\u52a8\u91ca\u653e\u5185\u5b58<\/span><\/p>\n

\u6765\u6e90\uff1astackoverflow<\/span>
\n2024-05-01 13:45:35<\/span>
\n<\/i>0\u6d4f\u89c8<\/span>
\n<\/i>\u6536\u85cf<\/span> <\/p>\n

\u54c8\u55bd\uff01\u5927\u5bb6\u597d\uff0c\u5f88\u9ad8\u5174\u53c8\u89c1\u9762\u4e86\uff0c\u6211\u662f\u7684\u4e00\u540d\u4f5c\u8005\uff0c\u4eca\u5929\u7531\u6211\u7ed9\u5927\u5bb6\u5e26\u6765\u4e00\u7bc7\u300a\u5982\u4f55\u5728golang\u4e2d\u624b\u52a8\u91ca\u653e\u5185\u5b58\u300b<\/span>\uff0c\u672c\u6587\u4e3b\u8981\u4f1a\u8bb2\u5230<\/span>\u7b49\u7b49\u77e5\u8bc6\u70b9\uff0c\u5e0c\u671b\u5927\u5bb6\u4e00\u8d77\u5b66\u4e60\u8fdb\u6b65\uff0c\u4e5f\u6b22\u8fce\u5927\u5bb6\u5173\u6ce8\u3001\u70b9\u8d5e\u3001\u6536\u85cf\u3001\u8f6c\u53d1! \u4e0b\u9762\u5c31\u4e00\u8d77\u6765\u770b\u770b\u5427\uff01<\/p>\n

\u95ee\u9898\u5185\u5bb9
\n <\/p>\n

\u4e0b\u9762\u662f\u8ba1\u7b97 c(36,8) \u5e76\u5c06\u7ed3\u679c\u4fdd\u5b58\u5230\u6587\u4ef6\u7684\u4ee3\u7801<\/p>\n

func combine_dfs(n int, k int) (ans [][]int) {\n    temp := []int{}\n    var dfs func(int)\n    dfs = func(cur int) {\n        if len(temp)+(n-cur+1) < k {\n            return\n        }\n        if len(temp) == k {\n            comb := make([]int, k)\n            copy(comb, temp)\n            ans = append(ans, comb)\n            return\n        }\n        temp = append(temp, cur)\n        dfs(cur + 1)\n        temp = temp[:len(temp)-1]\n        dfs(cur + 1)\n    }\n    dfs(1)\n    return\n}\n\nfunc docombin() {\n    fmt.printf(\"%v\\n\", \"calculator...\")\n    cst := []byte{}\n    for i := 'a'; i <= 'z'; i++ {\n        cst = append(cst, byte(i))\n    }\n    for i := '0'; i <= '9'; i++ {\n        cst = append(cst, byte(i))\n    }\n    n := 36\n    k := 8\n    arr := combine_dfs(n, k)\n    fmt.printf(\"%v\\n\", \"writefile...\")\n    file, _ := os.openfile(\"result.txt\", os.o_create|os.o_trunc|os.o_rdwr|os.o_append, 0666)\n    defer file.close()\n    for _, m := range arr {\n        b:= bytes.buffer{}\n        b.reset()\n        for _, i := range m {\n            b.writebyte(cst[i-1])\n        }\n        b.writebyte('\\n')\n        file.write(b.bytes())\n    }\n}<\/pre>\n
\u4f46\u662f\u6211\u5199\u6587\u4ef6\u592a\u6162\u4e86..<\/p>\n
\u6240\u4ee5\u6211\u60f3\u4f7f\u7528goroutine\u6765\u5199\u6587\u4ef6\uff08\u4f7f\u7528pool\u6765\u9650\u5236goroutine\u7684\u6570\u91cf\uff09\uff1a<\/p>\n
func docombin2() {\n    fmt.printf(\"%v\\n\", \"calculator...\")\n    cst := []byte{}\n    for i := 'a'; i <= 'z'; i++ {\n        cst = append(cst, byte(i))\n    }\n    for i := '0'; i <= '9'; i++ {\n        cst = append(cst, byte(i))\n    }\n    n := 36\n    k := 8\n    arr := combine_dfs(n, k)\n    fmt.printf(\"%v\\n\", \"writefile...\")\n    file, _ := os.openfile(\"result.txt\", os.o_create|os.o_trunc|os.o_rdwr|os.o_append, 0666)\n    defer file.close()\n    pool := make(chan int, 100)\n    for _, m := range arr {\n        go func(m []int) {\n            pool <- 1\n            b := bytes.buffer{}\n            b.reset()\n            for _, i := range m {\n                b.writebyte(cst[i-1])\n            }\n            b.writebyte('\\n')\n            file.write(b.bytes())\n            <-pool\n        }(m)\n    }\n}<\/pre>\n
\u4f46\u662f\u5185\u5b58\u7206\u70b8\u4e86<\/p>\n
\u6211\u5c1d\u8bd5\u4f7f\u7528sync.pool\u6765\u907f\u514d\u5b83\uff0c\u4f46\u5931\u8d25\u4e86\uff1a<\/p>\n
var bufPool = sync.Pool{\n    New: func() interface{} {\n        return new(bytes.Buffer)\n    },\n}\n\nfunc DoCombin() {\n    fmt.Printf(\"%v\\n\", \"calculator...\")\n    cst := []byte{}\n    for i := 'a'; i <= 'z'; i++ {\n        cst = append(cst, byte(i))\n    }\n    for i := '0'; i <= '9'; i++ {\n        cst = append(cst, byte(i))\n    }\n    n := 36\n    k := 8\n    arr := combine_dfs(n, k)\n    fmt.Printf(\"%v\\n\", \"writefile...\")\n    file, _ := os.OpenFile(\"result.txt\", os.O_CREATE|os.O_TRUNC|os.O_RDWR|os.O_APPEND, 0666)\n    defer file.Close()\n    pool := make(chan int, 100)\n    for _, m := range arr {\n        go func(m []int) {\n            pool <- 1\n            b, _ := bufPool.Get().(*bytes.Buffer)\n            b.Reset()\n            for _, i := range m {\n                b.WriteByte(cst[i-1])\n            }\n            b.WriteByte('\\n')\n            bufPool.Put(b)\n            file.Write(b.Bytes())\n            <-pool\n        }(m)\n    }\n}<\/pre>\n
\u6709\u4ec0\u4e48\u529e\u6cd5\u53ef\u4ee5\u907f\u514d\u5185\u5b58\u7206\u70b8\u5417\uff1f<\/p>\n
    \n
  • 1.\u4e3a\u4ec0\u4e48\u4f7f\u7528sync.pool\u540e\u65e0\u6cd5\u907f\u514d\uff1f<\/li>\n
  • 2.\u6709\u4ec0\u4e48\u529e\u6cd5\u53ef\u4ee5\u9650\u5236windows\u4e2d\u7684\u5185\u5b58\u4f7f\u7528\uff08\u6211\u77e5\u9053linux\u4e2d\uff09\uff1f<\/li>\n
  • 3.\u8fd8\u6709\u5176\u4ed6\u529e\u6cd5\u907f\u514d\u5185\u5b58\u7206\u70b8\u5417\uff1f<\/li>\n
  • 4.\u5185\u5b58\u7206\u70b8\u662f\u56e0\u4e3abytes.buffer\u5417\uff1f\u5982\u4f55\u624b\u52a8\u91ca\u653ebytes.buffer\uff1f<\/li>\n<\/ul>\n
     <\/p>\n
    \u6b63\u786e\u7b54\u6848<\/h2>\n
     <\/p>\n
    \u66f4\u65b0 2023 \u5e74 2 \u6708 20 \u65e5<\/p>\n
    \u7531\u4e8e\u4e25\u91cd\u7684 api \u95ee\u9898\uff0c\u6b64\u63d0\u6848 arenas<\/code> \u88ab\u65e0\u9650\u671f\u6401\u7f6e\u3002 goexperiment=arena<\/code> \u4ee3\u7801\u53ef\u80fd\u4f1a\u968f\u65f6\u4ee5\u4e0d\u517c\u5bb9\u7684\u65b9\u5f0f\u8fdb\u884c\u66f4\u6539\u6216\u5220\u9664\uff0c\u6211\u4eec\u4e0d\u5efa\u8bae\u5728\u751f\u4ea7\u4e2d\u4f7f\u7528\u5b83<\/strong>\u3002<\/p>\n
    \u6839\u636e\u8fd9\u4e2a<\/p>\n
    \u6211\u4eec\u5efa\u8bae\u5411 go \u6807\u51c6\u5e93\u6dfb\u52a0\u65b0\u7684 arena<\/code> \u5305\u3002\u7ade\u6280\u573a\u5305\u5c06\u5141\u8bb8\u5206\u914d\u4efb\u610f\u6570\u91cf\u7684\u7ade\u6280\u573a\u3002\u53ef\u4ee5\u4ecearena\u7684\u5185\u5b58\u4e2d\u5206\u914d\u4efb\u610f\u7c7b\u578b\u7684\u5bf9\u8c61\uff0c\u5e76\u4e14arena\u4f1a\u6839\u636e\u9700\u8981\u81ea\u52a8\u589e\u957f\u5927\u5c0f\u3002\u5f53arena\u4e2d\u7684\u6240\u6709\u5bf9\u8c61\u4e0d\u518d\u4f7f\u7528\u65f6\uff0c\u53ef\u4ee5\u663e\u5f0f\u91ca\u653earena\u4ee5\u6709\u6548\u5730\u56de\u6536\u5176\u5185\u5b58\uff0c\u800c\u65e0\u9700\u8fdb\u884c\u5e38\u89c4\u5783\u573e\u56de\u6536\u3002\u6211\u4eec\u8981\u6c42\u5b9e\u73b0\u63d0\u4f9b\u5b89\u5168\u68c0\u67e5\uff0c\u8fd9\u6837\uff0c\u5982\u679carena free\u64cd\u4f5c\u4e0d\u5b89\u5168\uff0c\u7a0b\u5e8f\u5c06\u5728\u4efb\u4f55\u4e0d\u6b63\u786e\u7684\u884c\u4e3a\u53d1\u751f\u4e4b\u524d\u7ec8\u6b62\u3002<\/p>\n
    \u6b64\u529f\u80fd\u5df2\u5408\u5e76\u5230 \u4e0b\u7684 master \u5206\u652f\uff0c\u4e5f\u8bb8<\/strong>\u53ef\u80fd\u4f1a\u5728 go 1.20 \u4e2d\u53d1\u5e03\u3002\u4f7f\u7528 arena<\/code> \u5305\uff0c\u60a8\u53ef\u4ee5\u81ea\u5df1\u5206\u914d\u5185\u5b58\uff0c\u5e76\u5728\u4e0d\u518d\u4f7f\u7528\u65f6\u624b\u52a8\u91ca\u653e\u5b83\u3002<\/p>\n<\/p>\n
        a := arena.NewArena()\n    defer a.Free()\n\n    tt := arena.New[T1](a)\n    tt.n = 1\n\n    ts := arena.MakeSlice[T1](a, 99, 100)\n    if len(ts) != 99 {\n        t.Errorf(\"Slice() len = %d, want 99\", len(ts))\n    }\n    if cap(ts) != 100 {\n        t.Errorf(\"Slice() cap = %d, want 100\", cap(ts))\n    }\n    ts[1].n = 42\n<\/pre>\n
    \u5728 1.19 \u4e2d<\/p>\n
    \u5783\u573e\u6536\u96c6\u5668\u6dfb\u52a0\u4e86\u5bf9\u8f6f\u5185\u5b58\u9650\u5236\u7684\u652f\u6301\uff0c<\/p>\n<\/p>\n
    \u7406\u8bba\u8981\u638c\u63e1\uff0c\u5b9e\u64cd\u4e0d\u80fd\u843d\uff01\u4ee5\u4e0a\u5173\u4e8e\u300a\u5982\u4f55\u5728golang\u4e2d\u624b\u52a8\u91ca\u653e\u5185\u5b58\u300b\u7684\u8be6\u7ec6\u4ecb\u7ecd\uff0c\u5927\u5bb6\u90fd\u638c\u63e1\u4e86\u5427\uff01\u5982\u679c\u60f3\u8981\u7ee7\u7eed\u63d0\u5347\u81ea\u5df1\u7684\u80fd\u529b\uff0c\u90a3\u4e48\u5c31\u6765\u5173\u6ce8\u516c\u4f17\u53f7\u5427\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
    \u5f53\u524d\u4f4d\u7f6e\uff1a > > ...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-208293","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/208293","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=208293"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/208293\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=208293"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=208293"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=208293"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}