博弈论练习2
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1.AGC010F - Tree Game
题目描述
Solution
一道简单博弈题(不知道为啥能作为AGC的F题)。
考虑树形dpdpdp,设f[x]f[x]f[x]表示以xxx为根的子树中是否先手必胜。
则f[x]=1f[x]=1f[x]=1当且仅当能找到xxx的子节点vvv满足f[v]=0f[v]=0f[v]=0且a[x]>a[v]a[x]>a[v]a[x]>a[v](因为这样就可以把后手摁死在vvv子树里,让后手输掉,自己就赢了)。
对于每一个结点都把它当做整一棵树的根dpdpdp一遍即可。
时间复杂度O(n2)O(n^2)O(n2)
#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <queue>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <cassert>
#include <string.h>
//#include <unordered_set>
//#include <unordered_map>
//#include <bits/stdc++.h>#define MP(A,B) make_pair(A,B)
#define PB(A) push_back(A)
#define SIZE(A) ((int)A.size())
#define LEN(A) ((int)A.length())
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define fi first
#define se secondusing namespace std;template<typename T>inline bool upmin(T &x,T y) { return y<x?x=y,1:0; }
template<typename T>inline bool upmax(T &x,T y) { return x<y?x=y,1:0; }typedef long long ll;
typedef unsigned long long ull;
typedef long double lod;
typedef pair<int,int> PR;
typedef vector<int> VI;const lod eps=1e-11;
const lod pi=acos(-1);
const int oo=1<<30;
const ll loo=1ll<<62;
const int mods=998244353;
const int MAXN=600005;
const int INF=0x3f3f3f3f;//1061109567
/*--------------------------------------------------------------------*/
inline int read()
{int f=1,x=0; char c=getchar();while (c<'0'||c>'9') { if (c=='-') f=-1; c=getchar(); }while (c>='0'&&c<='9') { x=(x<<3)+(x<<1)+(c^48); c=getchar(); }return x*f;
}
int a[MAXN],f[MAXN];
vector<int> e[MAXN];
bool dfs(int x,int father)
{for (auto v:e[x]){if (v==father) continue;dfs(v,x);if (a[x]>a[v]&&!f[v]) return f[x]=1;} return f[x]=0;
}
int main()
{int n=read();for (int i=1;i<=n;i++) a[i]=read();for (int i=1;i<n;i++){int u=read(),v=read();e[u].PB(v);e[v].PB(u);}for (int i=1;i<=n;i++)if (dfs(i,0)) printf("%d ",i);return 0;
}
2.SPOJ COT3 - Combat on a tree
题目描述
Solution
一道SG (数据结构)好题。
每一次选择一条到根的路径清零就相当于断成若干个独立的子树,因此就可以求子树SGSGSG值计算答案,用可持久化trietrietrie树维护整体xorxorxor和求mexmexmex。
#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <queue>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <cassert>
#include <string.h>
//#include <unordered_set>
//#include <unordered_map>
//#include <bits/stdc++.h>#define MP(A,B) make_pair(A,B)
#define PB(A) push_back(A)
#define SIZE(A) ((int)A.size())
#define LEN(A) ((int)A.length())
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define fi first
#define se secondusing namespace std;template<typename T>inline bool upmin(T &x,T y) { return y<x?x=y,1:0; }
template<typename T>inline bool upmax(T &x,T y) { return x<y?x=y,1:0; }typedef long long ll;
typedef unsigned long long ull;
typedef long double lod;
typedef pair<int,int> PR;
typedef vector<int> VI;const lod eps=1e-11;
const lod pi=acos(-1);
const int oo=1<<30;
const ll loo=1ll<<62;
const int mods=998244353;
const int MAXN=200005;
const int MAXM=MAXN<<5;
const int INF=0x3f3f3f3f;//1061109567
/*--------------------------------------------------------------------*/
inline int read()
{int f=1,x=0; char c=getchar();while (c<'0'||c>'9') { if (c=='-') f=-1; c=getchar(); }while (c>='0'&&c<='9') { x=(x<<3)+(x<<1)+(c^48); c=getchar(); }return x*f;
}
int sum[MAXN],c[MAXN],rt[MAXN],sg[MAXN],up[MAXN];
vector<int> e[MAXN],Ans;
struct Trie_Tree
{int nodenum=0,flag[MAXM],tag[MAXM],dep[MAXM],ch[MAXM][2];void up(int x) { flag[x]=flag[ch[x][0]]&&flag[ch[x][1]]; }void Xor(int x,int y) {if (!x) return;tag[x]^=y; if (y&(1<<(31-dep[x]-1))) swap(ch[x][0],ch[x][1]);}void down(int x){if (!x||!tag[x]) return;Xor(ch[x][0],tag[x]);Xor(ch[x][1],tag[x]);tag[x]=0;}void Insert(int &x,int y,int Dep) { if (!x) dep[x=++nodenum]=Dep;down(x);if (Dep==31) { flag[x]=1; return; } if (y&(1<<(31-dep[x]-1))) Insert(ch[x][1],y,Dep+1);else Insert(ch[x][0],y,Dep+1);up(x);}int Mex(int x){if (!x||dep[x]==31) return 0;if (flag[ch[x][0]]) return (1<<(31-dep[x]-1))+Mex(ch[x][1]);return Mex(ch[x][0]);}int Merge(int x,int y){if (!x||!y) return x+y;if (dep[x]==31) { flag[x]=flag[x]||flag[y]; return x; }down(x),down(y);ch[x][0]=Merge(ch[x][0],ch[y][0]);ch[x][1]=Merge(ch[x][1],ch[y][1]);up(x);return x;}
} Trie;
void tree_dp(int x,int father)
{for (auto v:e[x]){if (v==father) continue;tree_dp(v,x);sum[x]^=sg[v];}if (!c[x]) Trie.Insert(rt[x],sum[x],1);for (auto v:e[x]){if (v==father) continue;Trie.Xor(rt[v],sum[x]^sg[v]);rt[x]=Trie.Merge(rt[x],rt[v]);}sg[x]=Trie.Mex(rt[x]);
}
void getans(int x,int father)
{if (father) up[x]=up[father]^sum[father]^sg[x];
// cout<<x<<" "<<father<<" "<<sum[x]<<" "<<sg[x]<<" "<<up[x]<<endl;for (auto v:e[x]){if (v==father) continue;getans(v,x);}if ((!c[x])&&((up[x]^sum[x])==0)) Ans.PB(x);
}
int main()
{int n=read();for (int i=1;i<=n;i++) c[i]=read();for (int i=1;i<n;i++){int u=read(),v=read();e[u].PB(v);e[v].PB(u);} tree_dp(1,0);getans(1,0);if (!Ans.size()) { puts("-1"); return 0; }sort(Ans.begin(),Ans.end());for (auto v:Ans) printf("%d\n",v);return 0;
}
3.CF494E.Sharti
题目描述
Solution
典型的翻硬币博弈模型。
整体的SGSGSG值为所有单独一个格子为黑色的SGSGSG值的异或和。
离散化行,线段树维护列信息求解。
#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <queue>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <cassert>
#include <string.h>
//#include <unordered_set>
//#include <unordered_map>
//#include <bits/stdc++.h>#define MP(A,B) make_pair(A,B)
#define PB(A) push_back(A)
#define SIZE(A) ((int)A.size())
#define LEN(A) ((int)A.length())
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define fi first
#define se secondusing namespace std;template<typename T>inline bool upmin(T &x,T y) { return y<x?x=y,1:0; }
template<typename T>inline bool upmax(T &x,T y) { return x<y?x=y,1:0; }typedef long long ll;
typedef unsigned long long ull;
typedef long double lod;
typedef pair<int,int> PR;
typedef vector<int> VI;const lod eps=1e-11;
const lod pi=acos(-1);
const int oo=1<<30;
const ll loo=1ll<<62;
const int mods=998244353;
const int MAXN=100005;
const int INF=0x3f3f3f3f;//1061109567
/*--------------------------------------------------------------------*/
inline int read()
{int f=1,x=0; char c=getchar();while (c<'0'||c>'9') { if (c=='-') f=-1; c=getchar(); }while (c>='0'&&c<='9') { x=(x<<3)+(x<<1)+(c^48); c=getchar(); }return x*f;
}
int n,m,k,K;
struct anode{ int x,l,r,c; } a[MAXN];
int compare(anode x,anode y) { return x.x<y.x; }
int getans(int l,int r)
{l--;int ret=0;for (int i=1;i<=k;i<<=1) ret|=((r/i-l/i-(i*2<=k?r/i/2-l/i/2:0))&1)?i:0;return ret;
}
struct Segment_Tree
{int nodenum=0,ls[MAXN<<5],rs[MAXN<<5];struct segnode{ int c,ans,flag; } tree[MAXN<<5];void up(int x){if (tree[x].flag) tree[x].ans=tree[x].c;else tree[x].ans=tree[ls[x]].ans^tree[rs[x]].ans;}void change(int &x,int L,int R,int l,int r,int c){
// cout<<x<<" "<<L<<" "<<R<<" "<<l<<" "<<r<<endl;if (!x) x=++nodenum,tree[x].c=getans(L,R);if (L>=l&&R<=r) { tree[x].flag+=c,up(x); return; }int mid=(L+R)>>1;if (r<=mid) change(ls[x],L,mid,l,r,c);else if (l>mid) change(rs[x],mid+1,R,l,r,c);else change(ls[x],L,mid,l,mid,c),change(rs[x],mid+1,R,mid+1,r,c);up(x);}
} segment;
int main()
{m=read(),n=read(),k=read(),K=1;while (K<=k) K<<=1;for (int i=1;i<=n;i++){int x1=read(),y1=read(),x2=read(),y2=read();a[i*2-1]=(anode){x1,y1,y2,1};a[i*2]=(anode){x2+1,y1,y2,-1}; }sort(a+1,a+(n<<1)+1,compare);int ans=0,rt=0;for (int i=1;i<=(n<<1);i++){
// cout<<a[i].x<<" "<<a[i].l<<" "<<a[i].r<<" "<<a[i].c<<endl;if (a[i].x!=a[i-1].x){int x=getans(a[i-1].x,a[i].x-1),y=segment.tree[1].ans,sx=0,sy=0;
// cout<<"Ans:"<<a[i].x<<" "<<a[i].l<<" "<<a[i].r<<" "<<x<<" "<<y<<endl;for (int j=K;j;j>>=1){int sum=sx*sy;sx+=((x&j)>0),sy+=((y&j)>0);if ((sx*sy-sum)&1) ans^=j;}}segment.change(rt,1,m,a[i].l,a[i].r,a[i].c);}puts(ans?"Hamed":"Malek");return 0;
}
4.[ZROJ十连测 Day5].银
题目描述
Solution
有题解,思路神仙学不来,贴个程序溜了。
#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <queue>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <cassert>
#include <string.h>
//#include <unordered_set>
//#include <unordered_map>
//#include <bits/stdc++.h>#define MP(A,B) make_pair(A,B)
#define PB(A) push_back(A)
#define SIZE(A) ((int)A.size())
#define LEN(A) ((int)A.length())
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define fi first
#define se secondusing namespace std;template<typename T>inline bool upmin(T &x,T y) { return y<x?x=y,1:0; }
template<typename T>inline bool upmax(T &x,T y) { return x<y?x=y,1:0; }typedef long long ll;
typedef unsigned long long ull;
typedef long double lod;
typedef pair<int,int> PR;
typedef vector<int> VI;const lod eps=1e-11;
const lod pi=acos(-1);
const int oo=1<<30;
const ll loo=1ll<<62;
const int mods=998244353;
const int MAXN=600005;
const int INF=0x3f3f3f3f;//1061109567
/*--------------------------------------------------------------------*/
inline int read()
{int f=1,x=0; char c=getchar();while (c<'0'||c>'9') { if (c=='-') f=-1; c=getchar(); }while (c>='0'&&c<='9') { x=(x<<3)+(x<<1)+(c^48); c=getchar(); }return x*f;
}
char st[MAXN];
int cnt[30];
int lowbit(int x){ return x&(-x); }
int main()
{int n=read(),SG=0;scanf("%s",st+1);reverse(st+1,st+n+1);for (int i=1;i<=n;i++)if (st[i]=='1'){SG^=lowbit(i);for (int j=20;j>=0;j--) cnt[j]+=((i>>j)&1);}int Case=read();while (Case--){int x=n-read()+1,c;if (st[x]=='1') st[x]='0',c=-1;else st[x]='1',c=1;SG^=lowbit(x);for (int j=20;j>=0;j--) cnt[j]+=((x>>j)&1)*c;if (!SG) { puts("0"); continue; }int mx=20;while (!(SG>>mx)) mx--;printf("%d\n",cnt[mx]);}return 0;
}
5.CF1033GChip Game
题目描述
Solution
8会8会,留坑定补flagflagflag。