{"id":220,"date":"2026-07-25T21:44:50","date_gmt":"2026-07-25T13:44:50","guid":{"rendered":"https:\/\/huxiaole.cloud\/?p=220"},"modified":"2026-07-25T21:47:16","modified_gmt":"2026-07-25T13:47:16","slug":"p1108-usaco99fall-%e4%bd%8e%e4%bb%b7%e8%b4%ad%e4%b9%b0","status":"publish","type":"post","link":"https:\/\/huxiaole.cloud\/index.php\/2026\/07\/25\/p1108-usaco99fall-%e4%bd%8e%e4%bb%b7%e8%b4%ad%e4%b9%b0\/","title":{"rendered":"P1108 [USACO99FALL] \u4f4e\u4ef7\u8d2d\u4e70"},"content":{"rendered":"\n<h1 class=\"wp-block-heading\">P1108 [USACO99FALL] \u4f4e\u4ef7\u8d2d\u4e70<\/h1>\n\n\n\n<h2 class=\"wp-block-heading\">\u9898\u76ee\u63cf\u8ff0<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u201c\u4f4e\u4ef7\u8d2d\u4e70\u201d\u8fd9\u6761\u5efa\u8bae\u662f\u5728\u5976\u725b\u80a1\u7968\u5e02\u573a\u53d6\u5f97\u6210\u529f\u7684\u4e00\u534a\u89c4\u5219\u3002\u8981\u60f3\u88ab\u8ba4\u4e3a\u662f\u4f1f\u5927\u7684\u6295\u8d44\u8005\uff0c\u4f60\u5fc5\u987b\u9075\u5faa\u4ee5\u4e0b\u7684\u95ee\u9898\u5efa\u8bae:\u201c\u4f4e\u4ef7\u8d2d\u4e70\uff1b\u518d\u4f4e\u4ef7\u8d2d\u4e70\u201d\u3002\u6bcf\u6b21\u4f60\u8d2d\u4e70\u4e00\u652f\u80a1\u7968\uff0c\u4f60\u5fc5\u987b\u7528\u4f4e\u4e8e\u4f60\u4e0a\u6b21\u8d2d\u4e70\u5b83\u7684\u4ef7\u683c\u8d2d\u4e70\u5b83\u3002\u4e70\u7684\u6b21\u6570\u8d8a\u591a\u8d8a\u597d\uff01\u4f60\u7684\u76ee\u6807\u662f\u5728\u9075\u5faa\u4ee5\u4e0a\u5efa\u8bae\u7684\u524d\u63d0\u4e0b\uff0c\u6c42\u4f60\u6700\u591a\u80fd\u8d2d\u4e70\u80a1\u7968\u7684\u6b21\u6570\u3002\u4f60\u5c06\u88ab\u7ed9\u51fa\u4e00\u6bb5\u65f6\u95f4\u5185\u4e00\u652f\u80a1\u7968\u6bcf\u5929\u7684\u51fa\u552e\u4ef7\uff0c\u4f60\u53ef\u4ee5\u9009\u62e9\u5728\u54ea\u4e9b\u5929\u8d2d\u4e70\u8fd9\u652f\u80a1\u7968\u3002\u6bcf\u6b21\u8d2d\u4e70\u90fd\u5fc5\u987b\u9075\u5faa\u201c\u4f4e\u4ef7\u8d2d\u4e70\uff1b\u518d\u4f4e\u4ef7\u8d2d\u4e70\u201d\u7684\u539f\u5219\u3002\u5199\u4e00\u4e2a\u7a0b\u5e8f\u8ba1\u7b97\u6700\u5927\u8d2d\u4e70\u6b21\u6570\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u91cc\u662f\u67d0\u652f\u80a1\u7968\u7684\u4ef7\u683c\u6e05\u5355\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">$\\def\\arraystretch{1.5} \\begin{array}{|c|c|c|c|c|c|c|c|c|c|c|c|c|}\\hline \\textsf{\u65e5\u671f} &amp; 1 &amp; 2 &amp; 3 &amp; 4 &amp; 5 &amp; 6 &amp; 7 &amp; 8 &amp; 9 &amp; 10 &amp; 11 &amp; 12 \\cr\\hline \\textsf{\u4ef7\u683c} &amp; 68 &amp; 69 &amp; 54 &amp; 64 &amp; 68 &amp; 64 &amp; 70 &amp; 67 &amp; 78 &amp; 62&amp; 98 &amp; 87 \\cr\\hline \\end{array}$<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6700\u4f18\u79c0\u7684\u6295\u8d44\u8005\u53ef\u4ee5\u8d2d\u4e70\u6700\u591a 4 \u6b21\u80a1\u7968\uff0c\u53ef\u884c\u65b9\u6848\u4e2d\u7684\u4e00\u79cd\u662f\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">$\\def\\arraystretch{1.5} \\begin{array}{|c|c|c|c|c|}\\hline \\textsf{\u65e5\u671f} &amp; 2 &amp; 5 &amp; 6 &amp; 10 \\cr\\hline \\textsf{\u4ef7\u683c} &amp; 69 &amp; 68 &amp; 64 &amp; 62 \\cr\\hline \\end{array}$<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u8f93\u5165\u683c\u5f0f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u7b2c\u4e00\u884c\u5171\u4e00\u4e2a\u6574\u6570 $N\\ (1 \\le N \\le 5000)$\uff0c\u80a1\u7968\u53d1\u884c\u5929\u6570\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7b2c\u4e8c\u884c\u4e00\u884c N \u4e2a\u6574\u6570\uff0c\u662f\u6bcf\u5929\u7684\u80a1\u7968\u4ef7\u683c\u3002\u4fdd\u8bc1\u662f\u5927\u5c0f\u4e0d\u8d85\u8fc7 $2^{16}$ \u7684\u6b63\u6574\u6570\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u8f93\u51fa\u683c\u5f0f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u8f93\u51fa\u5171\u4e00\u884c\u4e24\u4e2a\u6574\u6570\uff0c\u5206\u522b\u4e3a\u6700\u5927\u8d2d\u4e70\u6b21\u6570\u548c\u62e5\u6709\u6700\u5927\u8d2d\u4e70\u6b21\u6570\u7684\u65b9\u6848\u6570\uff08\u6570\u636e\u4fdd\u8bc1 $ \\le 2^{31}\uff09\u5f53\u4e8c\u79cd\u65b9\u6848\u201c\u770b\u8d77\u6765\u4e00\u6837\u201d\u65f6\uff08\u5c31\u662f\u8bf4\u5b83\u4eec\u6784\u6210\u7684\u4ef7\u683c\u961f\u5217\u4e00\u6837\u7684\u65f6\u5019\uff09\uff0c\u8fd9 $ 2 \u79cd\u65b9\u6848\u88ab\u8ba4\u4e3a\u662f\u76f8\u540c\u7684\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u8f93\u5165\u8f93\u51fa\u6837\u4f8b #1<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">\u8f93\u5165 #1<\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>12\n68 69 54 64 68 64 70 67 78 62 98 87\n\n<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u8f93\u51fa #1<\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>4 2\n<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\">\u601d\u8def<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u9053\u9898\u96be\u5904\u5728\u4e8e\u8981\u6c42\u7edf\u8ba1\u62e5\u6709\u6700\u5927\u8d2d\u4e70\u6b21\u6570\u7684\u65b9\u6848\uff0c\u8fd9\u9053\u9898\u7684\u65f6\u95f4\u590d\u6742\u5ea6\u662fO(n^2)(n&lt;=5000),\u901a\u8fc7\u89c2\u5bdf\u5f97\u51fa\u8fd9\u9053\u9898\u7684\u8d2d\u4e70\u7b2ci\u652f\u80a1\u7968\u662f\u548c\u4e4b\u524d\u7684\u7b2cj\u652f\u80a1\u7968\u6709\u5173\u7684\uff0c\u6240\u4ee5\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u4e24\u6b21\u5faa\u73af\u6c42\u51fa\u4ee5\u7b2ci\u4e2a\u6570\u5b57\u4e3a\u7ed3\u5c3e\uff0c\u6700\u957f\u53ef\u4ee5\u6709\u591a\u5c11\u4e2a\u6570\u5b57<br>\u90a3\u4e48\u95ee\u9898\u6765\u4e86\uff0c\u6bd4\u65b9\u8bf4{5,4,4,3}\u5c31\u4f1a\u6709\u4e24\u4e2a{5,4,3}\uff0c\u957f\u5ea6\u4e3a3\uff0c\u6570\u91cf\u4e3a2\uff0c\u4f46\u662f\u90fd\u662f\u540c\u4e00\u79cd\u65b9\u6848<br>\u4e3a\u4e86\u89e3\u51b3\u8fd9\u4e2a\u95ee\u9898\uff0c\u6211\u4eec\u53ef\u4ee5\u628a\u524d\u7f00\u76f8\u540c\u7684\u6570\u5b57\u8fdb\u884c\u53bb\u91cd\uff0c\u90a3\u4e48\u4ed6\u4eec\u6709\u4ec0\u4e48\u5171\u540c\u70b9\u5462\uff0c\u5176\u5b9e\u5c31\u662f\u6570\u5b57\u76f8\u540c\u4e14\u524d\u7f00\u957f\u5ea6\u76f8\u540c\u3002<br>\u5904\u7406\u4e4b\u540e\u6211\u4eec\u53ea\u9700\u8981\u7edf\u8ba1\u6bcf\u4e2a\u76f8\u540c\u6570\u5b57\u7684\u4f4d\u7f6e\uff0c\u53ef\u4ee5\u7edf\u8ba1\u6210\u65b9\u6848\uff0c\u4e5f\u5c31\u662f\u6570\u7ec4cnt\uff0c\u6700\u540e\u53ea\u8981\u904d\u5386\u627e\u51fa\u62e5\u6709\u6700\u5927\u8d2d\u4e70\u6b21\u6570\u7684\u65b9\u6848\u6570\u91cf\u5373\u53ef<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/Sunshine&nbsp;sunshine&nbsp;ladybugs&nbsp;awake,  \n\/\/Clap&nbsp;your&nbsp;hooves&nbsp;and&nbsp;do&nbsp;a&nbsp;little&nbsp;shack.  \n#include&lt;bits\/stdc++.h&gt;  \n#define&nbsp;int&nbsp;long&nbsp;long  \n#define&nbsp;endl&nbsp;\"\\n\"  \n  \nusing&nbsp;namespace&nbsp;std;  \n  \nusing&nbsp;PII=pair&lt;int,int&gt;&nbsp;;  \nconst&nbsp;int&nbsp;MAXN=100010;  \nconst&nbsp;int&nbsp;mod=998244353;  \nconst&nbsp;int&nbsp;INF=0x3f3f3f3f3f3f3f3f;  \n  \nvoid&nbsp;solve(){  \n&nbsp;&nbsp;&nbsp;&nbsp;int&nbsp;n;cin&gt;&gt;n;  \n&nbsp;&nbsp;&nbsp;&nbsp;vector&lt;int&gt;&nbsp;a(n);  \n&nbsp;&nbsp;&nbsp;&nbsp;for(auto&nbsp;&amp;x:a)cin&gt;&gt;x;  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;vector&lt;int&gt;&nbsp;len(n,1);  \n&nbsp;&nbsp;&nbsp;&nbsp;for(int&nbsp;i=0;i&lt;n;i++){  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;for(int&nbsp;j=0;j&lt;i;j++){  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if(a&#91;j]&gt;a&#91;i]&amp;&amp;j&lt;i){  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;len&#91;i]=max(len&#91;i],len&#91;j]+1);  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}  \n&nbsp;&nbsp;&nbsp;&nbsp;}  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;int&nbsp;max_len=*max_element(len.begin(),len.end());  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;vector&lt;int&gt;&nbsp;cnt(n,0);  \n&nbsp;&nbsp;&nbsp;&nbsp;for(int&nbsp;i=0;i&lt;n;i++){  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if(len&#91;i]==1){  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;cnt&#91;i]=1;  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;for(int&nbsp;j=0;j&lt;i;j++){  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if(a&#91;j]&gt;a&#91;i]&amp;&amp;len&#91;j]+1==len&#91;i]){  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;cnt&#91;i]+=cnt&#91;j];  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}else&nbsp;if(a&#91;j]==a&#91;i]&amp;&amp;len&#91;j]==len&#91;i]){  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;cnt&#91;j]=0;  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}  \n&nbsp;&nbsp;&nbsp;&nbsp;}  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;int&nbsp;ways=0;  \n&nbsp;&nbsp;&nbsp;&nbsp;for(int&nbsp;i=0;i&lt;n;i++){  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if(len&#91;i]==max_len){  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ways+=cnt&#91;i];  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}  \n&nbsp;&nbsp;&nbsp;&nbsp;}  \n&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;cout&lt;&lt;max_len&lt;&lt;\"&nbsp;\"&lt;&lt;ways&lt;&lt;endl;  \n}  \n  \nsigned&nbsp;main()&nbsp;{  \n&nbsp;&nbsp;&nbsp;&nbsp;ios::sync_with_stdio(false);  \n&nbsp;&nbsp;&nbsp;&nbsp;cin.tie(nullptr);  \n&nbsp;&nbsp;&nbsp;&nbsp;\/\/int&nbsp;t;cin&gt;&gt;t;while(t--)  \n&nbsp;&nbsp;&nbsp;&nbsp;solve();  \n&nbsp;&nbsp;&nbsp;&nbsp;return&nbsp;0;  \n}\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>P1108 [USACO99FALL] \u4f4e\u4ef7\u8d2d\u4e70 \u9898\u76ee\u63cf\u8ff0 \u201c\u4f4e\u4ef7\u8d2d\u4e70\u201d\u8fd9\u6761\u5efa\u8bae\u662f\u5728\u5976\u725b\u80a1\u7968\u5e02\u573a\u53d6\u5f97\u6210\u529f\u7684\u4e00\u534a [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[17,18],"tags":[],"class_list":["post-220","post","type-post","status-publish","format-standard","hentry","category-dp","category-luogu"],"_links":{"self":[{"href":"https:\/\/huxiaole.cloud\/index.php\/wp-json\/wp\/v2\/posts\/220","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/huxiaole.cloud\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/huxiaole.cloud\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/huxiaole.cloud\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/huxiaole.cloud\/index.php\/wp-json\/wp\/v2\/comments?post=220"}],"version-history":[{"count":6,"href":"https:\/\/huxiaole.cloud\/index.php\/wp-json\/wp\/v2\/posts\/220\/revisions"}],"predecessor-version":[{"id":226,"href":"https:\/\/huxiaole.cloud\/index.php\/wp-json\/wp\/v2\/posts\/220\/revisions\/226"}],"wp:attachment":[{"href":"https:\/\/huxiaole.cloud\/index.php\/wp-json\/wp\/v2\/media?parent=220"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/huxiaole.cloud\/index.php\/wp-json\/wp\/v2\/categories?post=220"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/huxiaole.cloud\/index.php\/wp-json\/wp\/v2\/tags?post=220"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}