\u770b\u5230\\(DAG\\)\uff0c\u7acb\u523b\u53ef\u4ee5\u8003\u8651\u4e0a\u4e00\u4e2a\u62d3\u6251\u6392\u5e8f\u3002
\n\u5c06\u504f\u5e8f\u5173\u7cfb\u8f6c\u5316\u4e3a\u90bb\u63a5\u77e9\u9635\u5373\u53ef\u3002<\/p>\n
#include<iostream>\r\n#include<cstdio>\r\n#include<math.h>\r\n#include<string.h>\r\n#include<algorithm>\r\n#include<queue>\r\nusing namespace std;\r\nint n,m,s[1005][1005],in[1005],ans=0;\r\nbool map[1005][1005],a[1005],d[1005],used[1005];\r\nqueue <int> q;\r\n\r\nvoid re(){\r\n\twhile(1){\r\n\t\tbool bo=0;\r\n\t\tfor(int i=1;i<=n;i++){\r\n\t\t\tif(!in[i]&&!used[i]){\r\n\t\t\t\tq.push(i);\r\n\t\t\t\tused[i]=1;\r\n\t\t\t\tbo=1;\r\n\t\t\t}\r\n\t\t}\r\n\t\tif(!bo){\r\n\t\t\tbreak;\r\n\t\t}\r\n\t\twhile(!q.empty()){\r\n\t\t\tint p=q.front();\r\n\t\t\tq.pop();\r\n\t\t\tfor(int i=1;i<=n;i++){\r\n\t\t\t\tif(map[p][i]){\r\n\t\t\t\t\tmap[p][i]=0;\r\n\t\t\t\t\tin[i]--;\r\n\t\t\t\t}\r\n\t\t\t}\r\n\t\t}\r\n\t\tans++;\r\n\t}\r\n}\r\n\r\nint init(){\r\n\tmemset(in,0,sizeof(in));\r\n\tscanf(\"%d %d\",&n,&m);\r\n\tfor(int i=1;i<=m;i++){\r\n\t\tscanf(\"%d\",&s[i][0]);\r\n\t\tmemset(a,0,sizeof(a));\r\n\t\tfor(int j=1;j<=s[i][0];j++){\r\n\t\t\tscanf(\"%d\",&s[i][j]);\r\n\t\t\ta[s[i][j]]=1;\r\n\t\t}\r\n\t\tfor(int j=s[i][1];j<=s[i][s[i][0]];j++){\r\n\t\t\tif(!a[j]){\r\n\t\t\t\tfor(int k=1;k<=s[i][0];k++){\r\n\t\t\t\t\t\/\/map(i,j)\u8868\u793ai<j\r\n\t\t\t\t\tif(!map[j][s[i][k]]){\r\n\t\t\t\t\t\tmap[j][s[i][k]]=1;\r\n\t\t\t\t\t\tin[s[i][k]]++;\r\n\t\t\t\t\t}\r\n\t\t\t\t}\r\n\t\t\t}\r\n\t\t}\r\n\t}\r\n}\r\n\r\nint main(){\r\n\tinit();\r\n\tre();\r\n\tprintf(\"%d\",ans);\r\n}<\/code><\/pre>\n <\/p>\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
\u770b\u5230\\(DAG\\)\uff0c\u7acb\u523b\u53ef\u4ee5\u8003\u8651\u4e0a\u4e00\u4e2a\u62d3\u6251\u6392\u5e8f\u3002 \u5c06\u504f\u5e8f\u5173\u7cfb\u8f6c\u5316\u4e3a\u90bb\u63a5\u77e9\u9635\u5373\u53ef\u3002 #include<io … <\/p>\n