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@Plutorabbit 2017-02-19T03:05:55.000000Z 字数 7644 阅读 1777

HNOI 2016

未分类


BZOJ 4537 ~ BZOJ 4542

[Hnoi2016]最小公倍数

分块+并查集
就是零散的部分用并查集来维护
但是不能路径压缩
因为要暴力撤回去。。。

  1. #include <iostream>
  2. #include <cstdio>
  3. #include <algorithm>
  4. #include <cstdlib>
  5. #include <queue>
  6. #include <cmath>
  7. #include <cstring>
  8. #define NN 50010
  9. #define MM 100010
  10. using namespace std;
  11. struct Edge
  12. {
  13. int x,y,a,b,id;
  14. }e[MM],q[MM],tmp[MM];
  15. int fa[MM],n,m,sz[MM],Q,tot,ma[MM],mb[MM],block,k;
  16. bool vis[MM]={0};
  17. struct PRE
  18. {
  19. int x,y,sz,fa,yma,ymb,f,xma,xmb;
  20. }pre[MM];
  21. void read(int &xx)
  22. {
  23. bool f=0; char CH;
  24. for (CH=getchar();CH<'0'||CH>'9';CH=getchar()) if (CH=='-') f=1;
  25. for (xx=0;CH>='0';CH=getchar()) xx=xx*10+CH-'0'; if (f) xx=-xx;
  26. }
  27. bool cmp1(Edge xx,Edge yy) { if (xx.a==yy.a) return xx.b<yy.b; else return xx.a<yy.a;}
  28. bool cmp2(Edge xx,Edge yy) { if (xx.b==yy.b) return xx.a<yy.a; else return xx.b<yy.b;}
  29. int Find(int xx) { return (xx==fa[xx]?xx:Find(fa[xx]));}
  30. void Doit(int x,int y,int a,int b)
  31. {
  32. int xx=Find(x), yy=Find(y);
  33. if (sz[xx]>sz[yy]) swap(xx,yy);
  34. pre[++tot].x=xx, pre[tot].y=yy, pre[tot].f=fa[xx], pre[tot].sz=sz[yy];
  35. pre[tot].yma=ma[yy], pre[tot].ymb=mb[yy], pre[tot].xma=ma[xx], pre[tot].xmb=mb[xx];
  36. if (xx==yy)
  37. {
  38. ma[yy]=max(ma[yy],a), mb[yy]=max(mb[yy],b); return;
  39. }
  40. fa[xx]=yy, sz[yy]+=sz[xx], ma[yy]=max(ma[yy],max(ma[xx],a)), mb[yy]=max(mb[yy],max(mb[xx],b));
  41. }
  42. void Back()
  43. {
  44. for (;tot;tot--)
  45. {
  46. fa[pre[tot].x]=pre[tot].f, ma[pre[tot].x]=pre[tot].xma, mb[pre[tot].x]=pre[tot].xmb;
  47. sz[pre[tot].y]=pre[tot].sz, ma[pre[tot].y]=pre[tot].yma, mb[pre[tot].y]=pre[tot].ymb;
  48. }
  49. }
  50. int main()
  51. {
  52. read(n), read(m);
  53. for (int i=1;i<=m;++i) read(e[i].x), read(e[i].y), read(e[i].a), read(e[i].b), e[i].id=i;
  54. read(Q);
  55. for (int i=1;i<=Q;++i) read(q[i].x), read(q[i].y), read(q[i].a), read(q[i].b), q[i].id=i;
  56. sort(e+1,e+1+m,cmp1); sort(q+1,q+1+Q,cmp2);
  57. block=(int)sqrt(m);
  58. for (int i=1;i<=m;i+=block)
  59. {
  60. k=0;
  61. for (int j=1;j<=Q;++j)
  62. if (q[j].a>=e[i].a && (i+block>m || q[j].a<e[i+block].a)) tmp[++k]=q[j];
  63. if (!k) continue;
  64. sort(e+1,e+i,cmp2);
  65. for (int j=1;j<=n;++j) fa[j]=j, sz[j]=1, ma[j]=mb[j]=-1;
  66. for (int j=1,t=1;j<=k;++j)
  67. {
  68. for (;t<i && e[t].b<=tmp[j].b;t++) Doit(e[t].x,e[t].y,e[t].a,e[t].b);
  69. tot=0;
  70. for (int l=i;l<i+block&&l<=m;++l)
  71. if (e[l].a<=tmp[j].a && e[l].b<=tmp[j].b) Doit(e[l].x,e[l].y,e[l].a,e[l].b);
  72. int xx=Find(tmp[j].x), yy=Find(tmp[j].y);
  73. if (xx==yy && ma[xx]==tmp[j].a && mb[xx]==tmp[j].b) vis[tmp[j].id]=1;
  74. Back();
  75. }
  76. }
  77. for (int i=1;i<=Q;++i) if (vis[i]) puts("Yes"); else puts("No");
  78. return 0;
  79. }

[Hnoi2016]网络

树剖上乱搞

  1. #include <iostream>
  2. #include <cstdio>
  3. #include <cmath>
  4. #include <cstdlib>
  5. #include <cstring>
  6. #include <algorithm>
  7. #include <queue>
  8. #define INF 0x3f3f3f3f
  9. #define NN 100010
  10. using namespace std;
  11. struct Edge
  12. {
  13. int ne,u,v;
  14. }e[NN<<1];
  15. struct A
  16. {
  17. int x,y;
  18. }a[110];
  19. bool operator <(A xx,A yy) { return xx.x<yy.x;}
  20. int n,m,num,numm=0,tot=0,ans=0,cnt,now,x,y,op;
  21. int pos[NN],son[NN],fa[NN],sz[NN],deep[NN],head[NN],anc[NN];
  22. bool flag[NN<<1];
  23. priority_queue<A> que[300010];
  24. int read()
  25. {
  26. int xx; bool f=0; char CH;
  27. for (CH=getchar();CH<'0'||CH>'9';CH=getchar()) if (CH=='-') f=1;
  28. for (xx=0;CH>='0';CH=getchar()) xx=xx*10+CH-'0'; if (f) xx=-xx;
  29. return xx;
  30. }
  31. void Build(int xx,int yy)
  32. {
  33. e[++tot].ne=head[xx], head[xx]=tot, e[tot].v=yy, e[tot].u=xx;
  34. e[++tot].ne=head[yy], head[yy]=tot, e[tot].v=xx, e[tot].u=yy;
  35. }
  36. void DFS1(int xx)
  37. {
  38. sz[xx]=1;
  39. for (int i=head[xx];i;i=e[i].ne)
  40. if (e[i].v!=fa[xx])
  41. {
  42. fa[e[i].v]=xx, deep[e[i].v]=deep[xx]+1;
  43. DFS1(e[i].v);
  44. sz[xx]+=sz[e[i].v];
  45. if (sz[e[i].v]>sz[son[xx]]) son[xx]=e[i].v;
  46. }
  47. }
  48. void DFS2(int xx,int chain)
  49. {
  50. pos[xx]=++numm, anc[xx]=chain;
  51. if (son[xx]) DFS2(son[xx],chain);
  52. for (int i=head[xx];i;i=e[i].ne)
  53. if (e[i].v!=son[xx] && e[i].v!=fa[xx]) DFS2(e[i].v,e[i].v);
  54. }
  55. void Query(int k,int l,int r,int x)
  56. {
  57. while (!que[k].empty() && flag[que[k].top().y]) que[k].pop();
  58. if (!que[k].empty()) ans=max(ans,que[k].top().x);
  59. if (l<r)
  60. {
  61. int mid=(l+r)>>1;
  62. if (x<=mid) Query(k<<1,l,mid,x); else Query(k<<1|1,mid+1,r,x);
  63. }
  64. }
  65. void Insert(int k,int l,int r,int x,int y)
  66. {
  67. if (l==x && r==y) { que[k].push(A{num,now}); return; }
  68. int mid=(l+r)>>1;
  69. if (y<=mid) Insert(k<<1,l,mid,x,y);
  70. else if (x>mid) Insert(k<<1|1,mid+1,r,x,y);
  71. else Insert(k<<1,l,mid,x,mid), Insert(k<<1|1,mid+1,r,mid+1,y);
  72. }
  73. int main()
  74. {
  75. n=read(), m=read();
  76. for (int i=1;i<n;++i) x=read(), y=read(), Build(x,y);
  77. DFS1(1), DFS2(1,1);
  78. for (now=1;now<=m;++now)
  79. {
  80. op=read();
  81. if (op==0)
  82. {
  83. x=read(), y=read(), num=read(), cnt=0;
  84. for (;anc[x]!=anc[y];x=fa[anc[x]])
  85. {
  86. if (deep[anc[x]]<deep[anc[y]]) swap(x,y);
  87. a[++cnt].x=pos[anc[x]], a[cnt].y=pos[x];
  88. }
  89. if (deep[x]>deep[y]) swap(x,y);
  90. a[++cnt].x=pos[x], a[cnt].y=pos[y];
  91. sort(a+1,a+1+cnt);
  92. for (int i=1;i<=cnt;++i)
  93. if (a[i-1].y+1<a[i].x) Insert(1,1,n,a[i-1].y+1,a[i].x-1);
  94. if (a[cnt].y<n) Insert(1,1,n,a[cnt].y+1,n);
  95. }
  96. else if (op==1) flag[read()]=1;
  97. else ans=-1, Query(1,1,n,pos[read()]), printf("%d\n",ans);
  98. }
  99. return 0;
  100. }

[Hnoi2016]树

树上乱搞QAQ
感觉不想写就烂这了

[Hnoi2016]序列

莫队+rmq统计

  1. #include <iostream>
  2. #include <cstdio>
  3. #include <cmath>
  4. #include <cstdlib>
  5. #include <cstring>
  6. #include <algorithm>
  7. #include <queue>
  8. #define INF 0x3f3f3f3f
  9. #define NN 100010
  10. #define LL long long
  11. using namespace std;
  12. struct Query
  13. {
  14. int l,r,id;
  15. }q[NN];
  16. int st[NN],a[NN],l[NN],r[NN],f[NN][20],n,m,top=0,block,Log[NN];
  17. LL ans[NN],now,ld[NN],rd[NN];
  18. bool cmp1(Query xx,Query yy)
  19. {
  20. if (xx.l/block==yy.l/block) return xx.r<yy.r;
  21. else return xx.l/block<yy.l/block;
  22. }
  23. int read()
  24. {
  25. int xx; bool f=0; char CH;
  26. for (CH=getchar();CH<'0'||CH>'9';CH=getchar()) if (CH=='-') f=1;
  27. for (xx=0;CH>='0';CH=getchar()) xx=xx*10+CH-'0'; if (f) xx=-xx;
  28. return xx;
  29. }
  30. int Q(int x,int y)
  31. {
  32. int tmpp=(int)log2(y-x+1);
  33. if (a[f[x][tmpp]]<a[f[y-(1<<tmpp)+1][tmpp]]) return f[x][tmpp];
  34. else return f[y-(1<<tmpp)+1][tmpp];
  35. }
  36. void L_(int x,int y,LL t)
  37. {
  38. int tmp=Q(x,y);
  39. now+=t*a[tmp]*(y-tmp+1)+t*(rd[x]-rd[tmp]);
  40. }
  41. void R_(int x,int y,LL t)
  42. {
  43. int tmp=Q(x,y);
  44. now+=t*a[tmp]*(tmp-x+1)+t*(ld[y]-ld[tmp]);
  45. }
  46. void pre()
  47. {
  48. for (int i=1;i<=n;++i)
  49. {
  50. while (top && a[st[top]]>a[i]) r[st[top--]]=i;
  51. if (a[st[top]]==a[i]) l[i]=l[st[top]]; else l[i]=st[top];
  52. st[++top]=i;
  53. }
  54. while (top) r[st[top--]]=n+1;
  55. for (int i=1;i<=n;++i) ld[i]=ld[l[i]]+1ll*(i-l[i])*a[i];
  56. for (int i=n;i>=1;--i) rd[i]=rd[r[i]]+1ll*(r[i]-i)*a[i];
  57. for (int i=1;i<=n;++i) f[i][0]=i;
  58. for (int i=1;(1<<i)<=n;++i)
  59. for (int j=1;j<=n-(1<<i)+1;j++)
  60. {
  61. if (a[f[j][i-1]]<a[f[j+(1<<(i-1))][i-1]]) f[j][i]=f[j][i-1];
  62. else f[j][i]=f[j+(1<<(i-1))][i-1];
  63. }
  64. }
  65. int main()
  66. {
  67. n=read(), m=read();
  68. block=(int)sqrt(n);
  69. for (int i=1;i<=n;++i) a[i]=read();
  70. pre();
  71. for (int i=1;i<=m;++i) q[i].l=read(), q[i].r=read(), q[i].id=i;
  72. sort(q+1,q+1+m,cmp1);
  73. int x=1,y=1;
  74. now=a[1];
  75. for (int i=1;i<=m;++i)
  76. {
  77. if (q[i].r>y) while (y!=q[i].r) y++, R_(x,y,1);
  78. if (q[i].l>x) while (x!=q[i].l) L_(x,y,-1), x++;
  79. if (q[i].l<x) while (x!=q[i].l) x--, L_(x,y,1);
  80. if (q[i].r<y) while (y!=q[i].r) R_(x,y,-1), y--;
  81. ans[q[i].id]=now;
  82. }
  83. for (int i=1;i<=m;++i) printf("%lld\n",ans[i]);
  84. return 0;
  85. }

[Hnoi2016]矿区

听说对偶图乱搞QAQ
不会。。。
输出-1得10分蛤蛤

[Hnoi2016]大数

又双是莫队
时:统计下前缀和即可
时:暴力讨论即可

  1. #include <bits/stdc++.h>
  2. using namespace std;
  3. typedef long long LL;
  4. const int NN = 100005;
  5. struct Q
  6. {
  7. int l,r,id;
  8. }q[NN];
  9. LL mod,ans[NN],a[NN],bin[NN],b[NN],c[NN],pos[NN],cnt[NN],cnt2[NN],sum2[NN],now = 0;
  10. int tot,m,n,block;
  11. char ch[NN];
  12. inline bool cmp(Q xx,Q yy) { return (pos[xx.l] != pos[yy.l]) ? xx.l < yy.l : xx.r < yy.r; }
  13. inline void modify(int p,int op)
  14. {
  15. now -= cnt[b[p]] * (cnt[b[p]]-1) / 2;
  16. cnt[b[p]] += op;
  17. now += cnt[b[p]] * (cnt[b[p]]-1) / 2;
  18. }
  19. void Solve1()
  20. {
  21. block = (int) sqrt(n);
  22. bin[0] = 1; for (int i=1;i<=n+1;++i) bin[i] = bin[i-1] * 10ll % mod;
  23. for (int i=1;i<=n;++i) pos[i] = (i-1)/block + 1;
  24. for (int i=n;i;--i) b[i] = (b[i+1] + a[i] * bin[n-i]) % mod;
  25. b[n+1] = 0;
  26. memcpy(c,b,sizeof(c));
  27. sort(c+1,c+n+2);
  28. tot = unique(c+1,c+n+2) - c - 1;
  29. for (int i=1;i<=n+1;++i) b[i] = lower_bound(c+1,c+n+2,b[i]) - c;
  30. sort(q+1,q+m+1,cmp);
  31. for (int i=1,l=1,r=0;i<=m;++i)
  32. {
  33. for (;r<q[i].r;++r) modify(r+1,1);
  34. for (;r>q[i].r;--r) modify(r, -1);
  35. for (;l<q[i].l;++l) modify(l, -1);
  36. for (;l>q[i].l;--l) modify(l-1,1);
  37. ans[q[i].id] = now;
  38. }
  39. for (int i=1;i<=m;++i) printf("%lld\n",ans[i]);
  40. }
  41. void Solve2()
  42. {
  43. for (int i=1;i<=n;++i) cnt2[i] = cnt2[i-1] + (a[i] % mod == 0), sum2[i] = sum2[i-1] + (a[i]%mod == 0 ? i : 0);
  44. int x,y;
  45. for (int i=1;i<=m;++i)
  46. {
  47. x = q[i].l, y = q[i].r-1;
  48. printf("%lld\n",sum2[y] - sum2[x-1] - (LL)(x-1) * (cnt2[y]-cnt2[x-1]));
  49. }
  50. }
  51. int main()
  52. {
  53. scanf("%lld%s%d",&mod,ch+1,&m);
  54. n = strlen(ch+1);
  55. for (int i=1;i<=n;++i) a[i] = ch[i] - '0';
  56. for (int i=1;i<=m;++i) scanf("%d%d",&q[i].l,&q[i].r), ++q[i].r, q[i].id = i;
  57. if (mod == 2 || mod == 5) Solve2(); else Solve1();
  58. return 0;
  59. }
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