{"id":169,"date":"2018-10-20T00:24:17","date_gmt":"2018-10-19T16:24:17","guid":{"rendered":"http:\/\/SmokeyDays.top\/wordpress\/?p=169"},"modified":"2019-03-12T12:45:12","modified_gmt":"2019-03-12T04:45:12","slug":"lp3084-usaco13open-%e7%85%a7%e7%89%87-photo","status":"publish","type":"post","link":"http:\/\/SmokeyDays.top\/wordpress\/2018\/10\/20\/lp3084-usaco13open-%e7%85%a7%e7%89%87-photo\/","title":{"rendered":"lp3084 USACO13OPEN \u7167\u7247 Photo"},"content":{"rendered":"

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\n$$ s_{b+1}=Max(s_{b+1},a),e_{b}=Min(e_{b},a-1); $$
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\n$$ s_{i}=Max(s_{i},s_{i-1}); $$
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\n$$ e_{i}=Min(e_{i+1},e_{i}); $$
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\n\u4e8e\u662f\u95ee\u9898\u5f97\u89e3\u3002<\/p>\n

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#include<iostream>\n#include<cstdio>\n#include<queue>\nusing namespace std;\n#define Max(_A,_B) ((_A)>(_B)?(_A):(_B))\n#define Min(_A,_B) ((_A)<(_B)?(_A):(_B))\n\nint n,m,f[200005],s[200005],e[200005];\nstruct data{\n\tint v;\n\tint id;\n};\ndeque<data> q;\ninline void psh(int i){\n\tdata x=(data){f[i],i};\n\twhile(!q.empty()&&q.back().v<x.v){\n\t\tq.pop_back();\n\t}\n\tq.push_back(x);\n}\ninline int gt(const int &i){\n\twhile(!q.empty()&&q.front().id<s[i]){\n\t\tq.pop_front();\n\t}\n\treturn q.empty()?-1:q.front().v;\n}\nvoid init(){\n\tscanf(\"%d%d\",&n,&m);\n\tint a,b;\n\tfor(int i=1;i<=n+1;++i){\n\t\te[i]=i-1; \n\t}\n\tfor(int i=1;i<=m;++i){\n\t\tscanf(\"%d%d\",&a,&b);\n\t\ts[b+1]=Max(s[b+1],a),e[b]=Min(e[b],a-1);\n\t}\n\tfor(int i=2;i<=n+1;++i){\n\t\ts[i]=Max(s[i],s[i-1]);\n\t}\n\tfor(int i=n;i>=1;--i){\n\t\te[i]=Min(e[i+1],e[i]); \n\t}\n\tf[0]=0;\n\tpsh(0);\n\tint j=1,nw;\n\tfor(int i=1;i<=n+1;++i){\n\t\twhile(j<=e[i]&&j<=n){\n\t\t\tpsh(j);\n\t\t\t++j;\n\t\t}\n\t\tnw=gt(i);\n\t\tf[i]=(nw==-1)?-1:nw+(int)(i<=n);\n\t}\n\tprintf(\"%d\",f[n+1]);\n}\nint main(){\n\tinit();\n\treturn 0;\n}<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
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\u7ee7\u7eed\u9605\u8bfb\u201clp3084 USACO13OPEN \u7167\u7247 Photo\u201d<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[16,5],"tags":[],"_links":{"self":[{"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/posts\/169"}],"collection":[{"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/comments?post=169"}],"version-history":[{"count":2,"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/posts\/169\/revisions"}],"predecessor-version":[{"id":706,"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/posts\/169\/revisions\/706"}],"wp:attachment":[{"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/media?parent=169"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/categories?post=169"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/tags?post=169"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}