{"id":1317,"date":"2024-01-28T17:27:54","date_gmt":"2024-01-28T09:27:54","guid":{"rendered":"http:\/\/www.forillusion.com\/?p=1317"},"modified":"2025-02-14T11:39:10","modified_gmt":"2025-02-14T03:39:10","slug":"basic-algorithms-training50-4-search","status":"publish","type":"post","link":"https:\/\/www.forillusion.com\/index.php\/basic-algorithms-training50-4-search\/","title":{"rendered":"\u7b97\u6cd5\u57fa\u7840\u8bad\u7ec3 50 \u9898\uff08\u56db\uff09\u641c\u7d22"},"content":{"rendered":"\n

<\/div><\/p>\n\n\n\n

#JC0401. \u81ea\u7136\u6570\u7684\u62c6\u5206\u95ee\u9898<\/h2>\n\n\n\n

\u9898\u76ee\u63cf\u8ff0<\/a><\/p>\n\n\n\n

\u5229\u7528\u56de\u6eaf\u7b97\u6cd5\uff0c\u6bcf\u6b21\u90fd\u4ece1\u904d\u5386\u5230\u4e0a\u9650\uff0c\u5e76\u8bb0\u5f55\u5f53\u524d\u641c\u7d22\u7684\u503c\u4ee5\u53ca\u603b\u548c\u3002\u6bcf\u5f53\u603b\u548c\u7b49\u4e8en\u65f6\uff0c\u8f93\u51fa\u6240\u6709\u8bb0\u5f55\u7684\u503c\u3002<\/p>\n\n\n\n

using namespace std;\nint t,n,m,a[100],ans;\nstring s;\n\nint run(int l,int s,int sum)\n{\n\tif (sum==n)\n\t{\n\t\tif (s==1) return 0;\n\t\tfor (int i=1;i<s;i++)\n\t\t\tcout<<a[i]<<\"+\";\n\t\tcout<<a[s]<<endl;\n\t\treturn 0;\n\t}\n\n\ts++;\t\n\tfor (int i=l;i<=n;i++)\n\t{\n\t\ta[s]=i;\n\t\tif (sum+i>n) break;\n\t\trun(i,s,sum+i);\n\t}\n\treturn 0;\n}\n\nint main()\n{\n\tcin>>n;\n\trun(1,0,0);\n\treturn 0;\n} \n<\/code><\/pre>\n\n\n\n
#JC0402. \u516b\u7687\u540e\u95ee\u9898<\/h2>\n\n\n\n
\u9898\u76ee\u63cf\u8ff0<\/a><\/p>\n\n\n\n
\u5229\u7528\u56de\u6eaf\u7b97\u6cd5\uff0c\u56e0\u4e3a\u6bcf\u884c\u3001\u6bcf\u5217\u3001\u6bcf\u4e2a\u5bf9\u89d2\u7ebf\u90fd\u4e0d\u80fd\u653e\u7f6e\u68cb\u5b50\uff0c\u4f46\u662f\u641c\u7d22\u65f6\u662f\u6309\u884c\u4ece\u4e0a\u5f80\u4e0b\uff0c\u6240\u4ee5\u53ea\u9700\u8981\u7ef4\u62a4\u4e09\u4e2a\u6570\u7ec4\uff0c\u5206\u522b\u8bb0\u5f55\u522b\u6bcf\u5217\u3001\u6bcf\u4e2a\u5bf9\u89d2\u7ebf\u90fd\u662f\u5426\u653e\u8fc7\u68cb\u5b50\u3002\u5728\u653e\u7f6e\u68cb\u5b50\u65f6\uff0c\u7528x+y\u8868\u793a\u6240\u5728\u7684\u53f3\u659c\u5bf9\u89d2\u7ebf\uff0c\u7528x-y+n\u8868\u793a\u5de6\u659c\u5bf9\u89d2\u7ebf\uff08+n\u662f\u9632\u6b62\u7ed3\u679c\u4e3a\u8d1f\u6570\uff0c\u8d85\u51fa\u6570\u7ec4\u4e0b\u6807\u8303\u56f4\uff09<\/p>\n\n\n\n
int n,a[20],x[20],y[20],b1[50],b2[50],ans;\nint run(int i)\n{\n    if (i==n+1)\n    {\n        ans++;\n        if (ans>=4) return 0;\n        F(j,1,n)\n            CO a[j] P;\n        CL;\n        return 0;\n    }\n\n    for (int j=1;j<=n;j++)\n        if (!y[j]&&!b1[i+j]&&!b2[i-j+n])\n        {   \n            b1[i+j]=b2[i-j+n]=y[j]=1;\n            a[i]=j;\n            run(i+1);\n            b1[i+j]=b2[i-j+n]=y[j]=0;\n        }\n    return 0;\n}\nint main()\n{\n\tios::sync_with_stdio(0),cin.tie(0),cout.tie(0);\n    CI n;\n    run(1);\n    CO ans L;\n    return 0;\n}<\/code><\/pre>\n\n\n\n
#JC0403. Lake Counting S<\/h2>\n\n\n\n
\u9898\u76ee\u63cf\u8ff0<\/a><\/p>\n\n\n\n
\u8be5\u9898\u53ef\u4ee5\u7528\u591a\u6b21\u56de\u6eaf\u6765\u505a\uff0c\u6bcf\u4e00\u6b21\u56de\u6eaf\u90fd\u4f1a\u627e\u5230\u5e76\u6807\u8bb0\u8fde\u7eed\u7684W\uff0c\u5373\u4e00\u4e2a\u6c34\u5751\u91cc\u7684\u5168\u90e8W\uff0c\u800c\u5bf9\u6bcf\u4e2a\u6ca1\u6709\u88ab\u6807\u8bb0\u7684W\uff0c\u90fd\u8fdb\u884c\u4e00\u6b21\u56de\u6eaf\uff0c\u6700\u540e\u4f1a\u6807\u8bb0\u5b8c\u6240\u6709\u7684W\uff0c\u4e5f\u5c31\u627e\u5230\u4e86\u6240\u6709\u7684\u6c34\u5751\u3002<\/p>\n\n\n\n
\u7528\u6570\u7ec4a\u6765\u8868\u793a\u5730\u56fe\uff0c\u6570\u7ec4b\u6765\u8868\u793aw\u662f\u5426\u88ab\u6807\u8bb0\u8fc7\u3002\u6bcf\u6b21\u56de\u6eaf\u65f6\u90fd\u5c06\u80fd\u627e\u5230\u7684W\u5728b\u4e2d\u6807\u8bb0\uff0c\u6700\u540e\u518d\u904d\u5386\u6570\u7ec4a\uff0c\u7ed3\u5408\u6570\u7ec4b\u5bfb\u627e\u6ca1\u6709\u88ab\u6807\u8bb0\u8fc7\u7684W\uff0c\u8fdb\u884c\u4e0b\u4e00\u6b21\u56de\u6eaf\u3002<\/p>\n\n\n\n
int n,m,ans;\nint a[200][200],b[200][200];\nstring s;\n\nint run(int x,int y)\n{\n    int x1=max(1,x-1);\n    int y1=max(1,y-1);\n    int x2=min(n,x+1);\n    int y2=min(m,y+1);\n    F(i,x1,x2)\n        F(j,y1,y2)\n        {\n            if (i==x&&j==y) continue;\n            if (a[i][j]&&(!b[i][j]))\n            {\n                b[i][j]=1;\n                run(i,j);\n            }\n        }\n    return 0;\n}\n\nint main()\n{\n    \/\/ ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);\n    CI n>>m;\n    F(i,1,n)\n    {\n        CI s;\n        F(j,1,m)\n            if (s[j-1]=='W') a[i][j]=1;\n    }\n    F(i,1,n)\n    {\n        F(j,1,m)\n            if (a[i][j]&&(!b[i][j]))\n            {\n                run(i,j);\n                ans++;\n            }\n    }\n    CO ans L;\n    return 0;\n}<\/code><\/pre>\n\n\n\n
#JC0404. \u62ef\u6551oibh\u603b\u90e8<\/h2>\n\n\n\n
\u9898\u76ee\u63cf\u8ff0<\/a><\/p>\n\n\n\n
\u53ef\u4ee5\u5c06\u5730\u56fe\u6269\u5c55\u81f3(0,0)\u5230(n+1,m+1)\uff0c\u6700\u5916\u9762\u4e00\u5708\u586b\u51450\u4ee3\u8868\u6c34\u5751\uff0c\u7136\u540e\u4ece\u5750\u68070,0\u5f00\u59cb\uff0c\u641c\u7d22\u8fde\u7eed\u76840\u5e76\u6807\u8bb0\u3002\u6700\u540e\u518d\u904d\u5386\u6574\u4e2a\u5730\u56fe\uff0c\u8ba1\u6570\u6ca1\u6709\u6807\u8bb0\u4e14\u4e3a0\u7684\u533a\u57df\u6570\u91cf\u3002<\/p>\n\n\n\n
int n,m,a[501][501],b[501][501],ans;\nchar c;\n\nint run(int x,int y)\n{\n    if (x<0||x>n+1||y<0||y>m+1) return 0;\n    \n    int zx[4]={-1,0,1,0};\n    int zy[4]={0,-1,0,1};\n    F(i,0,3)\n    {\n        if (x+zx[i]>=0&&y+zy[i]>=0&&x+zx[i]<=n+1&&y+zy[i]<=m+1)\n            if (!a[x+zx[i]][y+zy[i]]&&!b[x+zx[i]][y+zy[i]]) \n            {\n                b[x+zx[i]][y+zy[i]]=1;\n                run(x+zx[i],y+zy[i]);\n            }\n    }\n    return 0;\n}\n\nint main()\n{\n    \/\/ ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);\n    CI n>>m;\n    F(i,1,n)\n        F(j,1,m)\n        {\n            CI c;\n            if (c=='*') a[i][j]=1;\n        }\n    \n    run(0,0);\n\n    F(i,1,n)\n        F(j,1,m)\n            if (!b[i][j]&&!a[i][j]) ans++;\n    CO ans L;\n    return 0;\n}<\/code><\/pre>\n\n\n\n
#JC0405. Need for Pink Slips<\/h2>\n\n\n\n
\u9898\u76ee\u63cf\u8ff0<\/a><\/p>\n\n\n\n
\u5229\u7528\u56de\u6eaf\uff0c\u6bcf\u6b21\u6309\u7167\u9898\u76ee\u8981\u6c42\u8c03\u6574c,m,p\u7684\u6982\u7387\u5e76\u5728\u9009\u4e2dp\u65f6\u7edf\u8ba1\u6982\u7387\u3002\u56de\u6eaf\u65f6\u4f20\u5165c,m,p\u7684\u6982\u7387\uff0c\u5f53\u524d\u62bd\u5956\u6b21\u6570\uff0c\u5f53\u524d\u7684\u603b\u6982\u7387\u3002<\/p>\n\n\n\n
int t;\ndouble c,m,p,v;\ndouble ans;\nstring s;\n\nint run(double c,double m,double p,double v,int t,double f)\n{\n    if (c!=0)\n    {\n        if (c-v<=1e-6)\n        {\n            \/\/ CO \"IN\" L;\n            if (m!=0.0) run(0.0,m+c\/2,p+c\/2,v,t+1,f*c);\n            else  run(0.0,0.0,1,v,t+1,f*c);\n        }\n        else \n        {\n            if (m!=0.0) run(c-v,m+v\/2,p+v\/2,v,t+1,f*c); \n            else run(c-v,0.0,p+v,v,t+1,f*c);\n        }\n    }\n    if (m!=0)\n    {\n        if (m-v<=1e-6)\n        {\n            if (c!=0.0) run(c+m\/2,0.0,p+m\/2,v,t+1,f*m);\n            else run(0.0,0.0,1,v,t+1,f*m);\n        }\n        else \n        {\n            if (c!=0.0) run(c+v\/2,m-v,p+v\/2,v,t+1,f*m);\n            else run(0.0,m-v,p+v,v,t+1,f*m);\n        }\n    }\n    if (p!=0)\n    {\n        f*=p;\n        t++;\n        ans+=t*f;\n    }\n    return 0;\n}\n\nint main()\n{\n    \/\/ ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);\n    CI t;\n    while (t--)\n    {\n        CI c>>m>>p>>v;\n        ans=0;\n        run(c,m,p,v,0,1);\n        printf(\"%.10lf\\n\",ans);\n    }\n    return 0;\n}<\/code><\/pre>\n\n\n\n
#JC0407. Catch That Cow S<\/h2>\n\n\n\n
\u9898\u76ee\u63cf\u8ff0<\/a><\/p>\n\n\n\n
\u672c\u9898\u5229\u7528\u5e7f\u5ea6\u4f18\u5148\u641c\u7d22bfs\uff0c\u4e0d\u65ad\u5224\u65ad\u4e0b\u4e00\u6b21\u79fb\u52a8\u662f\u5426\u4f1a\u8d85\u51fa\u79fb\u52a8\u6216\u5230\u8fbe\u5df2\u7ecf\u79fb\u52a8\u8fc7\u7684\u5730\u65b9\uff0c\u5e76\u5c06\u5176\u52a0\u5165\u5230\u961f\u5217\u4e2d\uff0c\u76f4\u5230\u6574\u4e2a\u5730\u56fe\u5168\u88ab\u641c\u7d22\u5b8c\uff0c\u7136\u540e\u8f93\u51fa\u725b\u6240\u5728\u7684\u5750\u6807\u7684\u641c\u7d22\u6df1\u5ea6\u3002<\/p>\n\n\n\n
int x,y,t;\nstruct Point\n{\n    int x,depth;\n    Point(int x,int depth):x(x),depth(depth){};\n};\n\nint main()\n{\n    \/\/ ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);\n    CI t;\n    while (t--)\n    {\n        CI x>>y;\n        int v[MAX+10]={0};\n        queue<Point> q;\n        v[x]=1;\n        q.push(Point(x,0));\n        while (!q.empty())\n        {\n            Point p=q.front();\n            if (p.x==y)\n            {\n                CO p.depth L;\n                break;\n            }\n\n            if (p.x-1>=0&&!v[p.x-1])\n            {\n                q.push(Point(p.x-1,p.depth+1));\n                v[p.x-1]=1;\n            }\n            if (p.x+1<=MAX&&!v[p.x+1])\n            {\n                q.push(Point(p.x+1,p.depth+1));\n                v[p.x+1]=1;\n            }\n            if (p.x*2<=MAX&&!v[p.x*2])\n            {\n                q.push(Point(p.x*2,p.depth+1));\n                v[p.x*2]=1;\n            }\n            q.pop();\n        }\n    }\n    return 0;\n}<\/code><\/pre>\n\n\n\n
#JC0408. \u9a6c\u7684\u904d\u5386<\/h2>\n\n\n\n
\u9898\u76ee\u63cf\u8ff0<\/a><\/p>\n\n\n\n
\u672c\u4f53\u5229\u7528dfs\uff0c\u4e0d\u65ad\u5224\u65ad\u4e0b\u4e00\u6b21\u9a6c\u79fb\u52a8\u662f\u5426\u4f1a\u8d85\u51fa\u79fb\u52a8\u6216\u5230\u8fbe\u5df2\u7ecf\u79fb\u52a8\u8fc7\u7684\u5730\u65b9\uff0c\u5e76\u5c06\u5176\u52a0\u5165\u5230\u961f\u5217\u4e2d\uff0c\u76f4\u5230\u6574\u4e2a\u5730\u56fe\u5168\u88ab\u641c\u7d22\u5b8c\uff0c\u7136\u540e\u8f93\u51fa\u6bcf\u4e2a\u5750\u6807\u7684\u641c\u7d22\u6df1\u5ea6\u3002 <\/p>\n\n\n\n
int v[MAX+10][MAX+10]={-1,-1};\nint n,m,x,y;\nint f[8][2]={{-2,-1},{-1,-2},{-2,1},{-1,2},{1,-2},{2,-1},{1,2},{2,1}};\nstruct Point\n{\n    int x,y,depth;\n    Point(int x,int y,int depth):x(x),y(y),depth(depth){};\n};\nqueue<Point> q;\nint main()\n{\n    \/\/ ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);\n    CI n>>m>>x>>y;\n    \n    q.push(Point(x,y,0));\n\n    F(i,1,n)\n    {\n        F(j,1,m)\n            v[i][j]=-1;\n    }\n    v[x][y]=0;\n\n    while (!q.empty())\n    {\n        Point p=q.front();\n\n        F(i,0,7)\n        {\n            if (p.x+f[i][0]>=1&&p.x+f[i][0]<=MAX&&p.y+f[i][1]>=1&&p.y+f[i][1]<=MAX&&v[p.x+f[i][0]][p.y+f[i][1]]==-1)\n            {\n                q.push(Point(p.x+f[i][0],p.y+f[i][1],p.depth+1));\n                v[p.x+f[i][0]][p.y+f[i][1]]=p.depth+1;\n            }\n        }\n        q.pop();\n    }\n    F(i,1,n)\n    {\n        F(j,1,m)\n            CO v[i][j]<<\"\\t\";\n        CL\n    }\n    return 0;\n}<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
#JC0401. \u81ea\u7136\u6570\u7684\u62c6\u5206\u95ee\u9898 \u9898\u76ee\u63cf\u8ff0 \u5229\u7528\u56de\u6eaf\u7b97\u6cd5\uff0c\u6bcf\u6b21\u90fd\u4ece1\u904d\u5386\u5230\u4e0a\u9650\uff0c\u5e76\u8bb0\u5f55\u5f53\u524d\u641c\u7d22\u7684\u503c\u4ee5\u53ca\u603b\u548c\u3002\u6bcf\u5f53\u603b\u548c\u7b49\u4e8en\u65f6\uff0c\u8f93 …<\/p>","protected":false},"author":1,"featured_media":1321,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3,35],"tags":[12,34,22,39],"class_list":["post-1317","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-3","category-35","tag-12","tag-34","tag-22","tag-39"],"_links":{"self":[{"href":"https:\/\/www.forillusion.com\/index.php\/wp-json\/wp\/v2\/posts\/1317","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.forillusion.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.forillusion.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.forillusion.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.forillusion.com\/index.php\/wp-json\/wp\/v2\/comments?post=1317"}],"version-history":[{"count":1,"href":"https:\/\/www.forillusion.com\/index.php\/wp-json\/wp\/v2\/posts\/1317\/revisions"}],"predecessor-version":[{"id":1738,"href":"https:\/\/www.forillusion.com\/index.php\/wp-json\/wp\/v2\/posts\/1317\/revisions\/1738"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.forillusion.com\/index.php\/wp-json\/wp\/v2\/media\/1321"}],"wp:attachment":[{"href":"https:\/\/www.forillusion.com\/index.php\/wp-json\/wp\/v2\/media?parent=1317"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.forillusion.com\/index.php\/wp-json\/wp\/v2\/categories?post=1317"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.forillusion.com\/index.php\/wp-json\/wp\/v2\/tags?post=1317"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}