{"id":453,"date":"2018-12-03T16:28:50","date_gmt":"2018-12-03T08:28:50","guid":{"rendered":"http:\/\/SmokeyDays.top\/wordpress\/?p=453"},"modified":"2018-12-03T16:28:50","modified_gmt":"2018-12-03T08:28:50","slug":"lp2679-noip2015-%e5%ad%90%e4%b8%b2","status":"publish","type":"post","link":"http:\/\/SmokeyDays.top\/wordpress\/2018\/12\/03\/lp2679-noip2015-%e5%ad%90%e4%b8%b2\/","title":{"rendered":"lp2679 NOIP2015 \u5b50\u4e32"},"content":{"rendered":"

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\n\\(f_{i,j,k}=(A_{k}==B_{i})*f_{i-1,j,k-1}+\\sum_{S=i}^{k}f_{i-1,j-1,S}\\)
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#include<iostream>\r\n#include<cstdio>\r\n\/* \r\n\r\n*\/\r\nconst long long MOD=1000000007;\r\n\r\nint n,m,K;\r\nlong long f[2][205][1005],sm[2][205][1005];\r\nchar A[1005],B[205];\r\nvoid init(){\r\n    scanf(\"%d%d%d\",&n,&m,&K);\r\n    std::cin>>(A+1)>>(B+1);\r\n    int nw=1;sm[0][0][0]=1;\r\n    for(int i=1;i<=n;++i){\r\n    \tsm[nw][0][0]=1;\r\n    \tfor(int j=1;j<=m;++j){\r\n    \t\tfor(int k=1;k<=K;++k){\r\n    \t\t\tf[nw][j][k]=(A[i]==B[j])?((f[nw^1][j-1][k]+sm[nw^1][j-1][k-1])%MOD):0;\r\n    \t\t\tsm[nw][j][k]=(sm[nw^1][j][k]+f[nw][j][k])%MOD;\r\n\t\t\t}\r\n\t\t}\r\n\t\tnw^=1;\r\n\t}\r\n    printf(\"%lld\\n\",sm[nw^1][m][K]);\r\n}\r\n\r\nint main(){\r\n    init();\r\n    return 0;\r\n}<\/code><\/pre>\n
 <\/p>\n","protected":false},"excerpt":{"rendered":"
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\u7ee7\u7eed\u9605\u8bfb\u201clp2679 NOIP2015 \u5b50\u4e32\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":[10,34,6,5],"tags":[],"_links":{"self":[{"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/posts\/453"}],"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=453"}],"version-history":[{"count":1,"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/posts\/453\/revisions"}],"predecessor-version":[{"id":454,"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/posts\/453\/revisions\/454"}],"wp:attachment":[{"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/media?parent=453"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/categories?post=453"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/SmokeyDays.top\/wordpress\/wp-json\/wp\/v2\/tags?post=453"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}