b:[["$","script",null,{"type":"application/ld+json","dangerouslySetInnerHTML":{"__html":"{\"@context\":\"https://schema.org\",\"@type\":\"Quiz\",\"name\":\"三元组\",\"description\":\"给定长度为 N 的数组，元素只能为 1,2,3，求满足 1≤i\n#include \nusing namespace std;\nint main() {\n ios::sync_with_stdio(false);\n cin.tie(nullptr);\n int N;\n cin >> N;\n vector a(N);\n for (int i = 0; i < N; ++i) cin >> a[i];\n int ans = 0;\n for (int j = 1; j < N - 1; ++j) {\n int left = 0, right = 0;\n for (int i = 0; i < j; ++i)\n if (a[i] < a[j]) left++;\n for (int k = j + 1; k < N; ++k)\n if (a[j] < a[k]) right++;\n ans += left * right;\n }\n cout << ans << '\\n';\n return 0;\n}","cppCodeAiGenerate":"","createdBy":703,"createdTime":"2025-08-14 19:06:05","creatorName":"","delFlag":0,"description":"给定长度为 N 的数组，元素只能为 1,2,3，求满足 1≤i6 \n1 3 2 1 2 3 \n3 \n","gid":null,"hideInNext":0,"hint":"无 \n","id":11062,"input":"第一行 N；第二行 N 个整数。 \n","ioReadFileName":"","ioScore":100,"ioWriteFileName":"","isFileIo":0,"isGroup":0,"isRemote":0,"isRemoveEndBlank":1,"isUploadCase":0,"judgeCaseMode":"default","judgeExtraFile":"","judgeMode":"default","memoryLimit":256,"modifiedUser":"","openCaseResult":1,"output":"一个整数，满足条件的三元组个数。 \n","problemBankId":null,"problemId":"","problemType":0,"pythonCode":"import sys\ninput = sys.stdin.readline\ndata = list(map(int, sys.stdin.read().split()))\nN = data[0]\na = data[1:N + 1]\nans = 0\nfor j in range(1, N - 1):\n left = sum(1 for i in range(j) if a[i] < a[j])\n right = sum(1 for k in range(j + 1, N) if a[j] < a[k])\n ans += left * right\nprint(ans)","revision":null,"source":"","spjCode":"","spjLanguage":"","stackLimit":128,"teamId":null,"tenantId":-1,"timeLimit":1000,"title":"三元组","type":0,"updatedBy":703,"updatedTime":"2025-08-14 19:06:05","userExtraFile":"","uuid":"65330713-1dbe-4465-beeb-42fea9c02454"},"specialId":null,"specialTitle":"","statistics":{"acceptAmt":0,"acceptUserAmt":0,"categoryName":"","collectAmt":0,"commentAmt":0,"commitAmt":0,"commitUserAmt":0,"createdBy":0,"createdTime":"2025-08-14 19:18:29","creatorName":"","dataId":11062,"dataType":2,"delFlag":0,"id":2640,"likeAmt":0,"updatedBy":0,"updatedTime":"2025-08-14 19:18:29","viewAmt":0},"tags":[{"categoryId":152,"categoryName":"","createdBy":0,"createdTime":"2025-01-05 18:50:09","creatorName":"","delFlag":0,"id":96,"isKnowledgeTag":1,"name":"枚举","revision":null,"subjectAmt":0,"tagGroupId":5,"tenantId":-1,"type":2,"updatedBy":0,"updatedTime":"2025-01-05 18:50:09"},{"categoryId":142,"categoryName":"","createdBy":0,"createdTime":"2025-01-05 21:17:50","creatorName":"","delFlag":0,"id":131,"isKnowledgeTag":1,"name":"前缀和","revision":null,"subjectAmt":0,"tagGroupId":3,"tenantId":-1,"type":2,"updatedBy":0,"updatedTime":"2025-01-05 21:17:50"},{"categoryId":144,"categoryName":"","createdBy":703,"createdTime":"2025-06-13 14:50:44","creatorName":"","delFlag":0,"id":945,"isKnowledgeTag":0,"name":"C++","revision":null,"subjectAmt":0,"tagGroupId":1,"tenantId":-1,"type":2,"updatedBy":703,"updatedTime":"2025-06-13 14:50:44"},{"categoryId":null,"categoryName":"","createdBy":703,"createdTime":"2025-08-11 17:04:49","creatorName":"","delFlag":0,"id":1077,"isKnowledgeTag":0,"name":"基础语法","revision":null,"subjectAmt":0,"tagGroupId":1,"tenantId":-1,"type":2,"updatedBy":703,"updatedTime":"2025-08-11 17:04:49"}]}}]]

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11062.三元组

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