21牛客多校第三場
這場好難 \(dls\)下手也太狠了
A
好奇怪的題 棄了
B
將每個點認為是邊和列之間的邊,容易發現題意即為求最小生成樹
因為邊權不會太大,桶排序後\(kruskal\)即可
#include<bits/stdc++.h> #define inf 2139062143 #define ll long long #define db double #define ld long double #define ull unsigned long long #define MAXN 100100 #define MOD 998244353 #define Fill(a,x) memset(a,x,sizeof(a)) #define rep(i,s,t) for(int i=(s),i##end=(t);i<=i##end;++i) #define dwn(i,s,t) for(int i=(s),i##end=(t);i>=i##end;--i) #define ren for(int i=fst[x];i;i=nxt[i]) #define pls(a,b) (a+b)%p #define mul(a,b) (1LL*(a)*(b))%p #define pii pair<int,int> #define fi first #define se second #define pb push_back using namespace std; inline int read() { int x=0,f=1;char ch=getchar(); while(!isdigit(ch)) {if(ch=='-') f=-1;ch=getchar();} while(isdigit(ch)) {x=x*10+ch-'0';ch=getchar();} return x*f; } int n,m,a,b,c,d,p,las,fa[MAXN],ans; vector<pii> e[MAXN]; int find(int x){return x==fa[x]?x:fa[x]=find(fa[x]);} inline int merge(int u,int v) { int fu=find(u),fv=find(v); if(fu!=fv) return fa[fu]=fv;return 0; } int main() { n=read(),m=read(),las=a=read(),b=read(),c=read(),d=read(),p=read(); rep(i,1,n) rep(j,1,m) { las=pls(pls(mul(mul(las,las),b),mul(las,c)),d); e[las].pb({i,j+n}); } rep(i,1,n+m) fa[i]=i; rep(i,0,p-1) for(auto t:e[i]) if(merge(t.fi,t.se)) ans+=i; printf("%d\n",ans); }
C
至多\(2n\)個點就一定可以滿足要求,而能減小答案的點一定滿足該點所在行和列限制相同
這樣的話對於這種點行與列連邊,做最大費用流即可
#include<bits/stdc++.h> #define inf 213906214300000LL #define ll long long #define db double #define ld long double #define ull unsigned long long #define MAXN 1001001 #define MAXM 1001001 #define Fill(a,x) memset(a,x,sizeof(a)) #define rep(i,s,t) for(int i=(s),i##end=(t);i<=i##end;++i) #define dwn(i,s,t) for(int i=(s),i##end=(t);i>=i##end;--i) #define ren for(int i=fst[x];i;i=nxt[i]) #define pls(a,b) (a+b)%MOD #define mns(a,b) (a-b+MOD)%MOD #define mul(a,b) (1LL*(a)*(b))%MOD #define pii pair<int,int> #define fi first #define se second #define pb push_back using namespace std; inline int read() { int x=0,f=1;char ch=getchar(); while(!isdigit(ch)) {if(ch=='-') f=-1;ch=getchar();} while(isdigit(ch)) {x=x*10+ch-'0';ch=getchar();} return x*f; } int n,m,k,a[MAXN],b[MAXN]; ll ans; struct ZKW { int nxt[MAXM<<1],to[MAXM<<1],val[MAXM<<1],cnt,fst[MAXN]; int vis[MAXN],S,T;queue<int> q; ll cst[MAXM<<1],dis[MAXN],res; void mem(){Fill(fst,0);cnt=1,res=0;} void add(int u,int v,int w,int c) {nxt[++cnt]=fst[u],fst[u]=cnt,to[cnt]=v,val[cnt]=w,cst[cnt]=c;} void ins(int u,int v,int w,int c) {add(u,v,w,c),add(v,u,0,-c);} int spfa() { int x;rep(i,1,n*2+2) dis[i]=-inf,vis[i]=0; dis[T]=0,vis[T]=1;q.push(T);while(!q.empty()) { x=q.front(),q.pop();vis[x]=0;ren if(dis[to[i]]<dis[x]-cst[i]&&val[i^1]) {dis[to[i]]=dis[x]-cst[i];if(!vis[to[i]]) vis[to[i]]=1,q.push(to[i]);} } return dis[S]!=-inf; } int dfs(int x,int a) { if(vis[x]) return 0;vis[x]=1;if(x==T||!a) {res+=a*dis[S];return a;} int f,flw=0;ren if(val[i]&&dis[to[i]]==dis[x]-cst[i]&&(f=dfs(to[i],min(a,val[i])))) a-=f,val[i]-=f,val[i^1]+=f,flw+=f; return flw; } int solve() { int f,flw=0;while(spfa()) do{memset(vis,0,sizeof(vis));f=dfs(S,inf),flw+=f;}while(f); return res; } }Z; int main() { n=read(),m=read(),k=read();int x,y; rep(i,1,n) a[i]=read(),ans+=a[i]; rep(i,1,n) b[i]=read(),ans+=b[i]; Z.mem();Z.S=2*n+1,Z.T=2*n+2; rep(i,1,n) Z.ins(Z.S,i,1,0),Z.ins(n+i,Z.T,1,0); rep(i,1,m) {x=read(),y=read();if(a[x]==b[y]) Z.ins(x,y+n,1,a[x]);} printf("%d\n",ans-Z.solve()); }
D
容斥+三維揹包 咕了
E
打表題(bushi
不難發現每一對數對是連續的,且\(a_i=x^2 a_{i-1}-a_{i-2}\),其中\((x,x^3)\)為這一條鏈的起始數對
最後\(upper\_bound\)即可
(也可以正經做,但是懶得再推一遍了,反正結論就是這個
#include<bits/stdc++.h> #define inf 2139062143 #define ll long long #define db double #define ld long double #define ull unsigned long long #define MAXN 10010010 #define MOD 998244353 #define Fill(a,x) memset(a,x,sizeof(a)) #define rep(i,s,t) for(int i=(s),i##end=(t);i<=i##end;++i) #define dwn(i,s,t) for(int i=(s),i##end=(t);i>=i##end;--i) #define ren for(int i=fst[x];i;i=nxt[i]) #define pls(a,b) (a+b)%MOD #define mns(a,b) (a-b+MOD)%MOD #define mul(a,b) (1LL*(a)*(b))%MOD #define pii pair<int,int> #define fi first #define se second #define pb push_back using namespace std; inline ll read() { ll x=0,f=1;char ch=getchar(); while(!isdigit(ch)) {if(ch=='-') f=-1;ch=getchar();} while(isdigit(ch)) {x=x*10+ch-'0';ch=getchar();} return x*f; } ll g[MAXN],n,ans;int tot; void mem(int n=1e6,ll lim=1e18) { __int128 x,y,z;g[++tot]=1; rep(i,2,n) { x=i,y=1LL*i*i*i; while(y<=lim) g[++tot]=y,z=y*i*i-x,x=y,y=z; } sort(g+1,g+tot+1); } int main() { mem();rep(T,1,read()) { n=read();ans=upper_bound(g+1,g+tot+1,n)-g-1; printf("%d\n",ans); } }
F
爆搜題
可以發現\(n\le 3\)時顯然不可能所有操作出現分數,直接判斷
先搜出\(4\)個數的組合,再排列後列舉所有的符號組合
判斷能湊出答案的所有方案是否都出現分數即可
#include<bits/stdc++.h>
#define inf 2139062143
#define ll long long
#define db double
#define ld long double
#define ull unsigned long long
#define MAXN 100100
#define MOD 998244353
#define Fill(a,x) memset(a,x,sizeof(a))
#define rep(i,s,t) for(int i=(s),i##end=(t);i<=i##end;++i)
#define dwn(i,s,t) for(int i=(s),i##end=(t);i>=i##end;--i)
#define ren for(int i=fst[x];i;i=nxt[i])
#define pls(a,b) (a+b)%MOD
#define mns(a,b) (a-b+MOD)%MOD
#define mul(a,b) (1LL*(a)*(b))%MOD
#define pii pair<int,int>
#define fi first
#define se second
#define pb push_back
using namespace std;
inline int read()
{
int x=0,f=1;char ch=getchar();
while(!isdigit(ch)) {if(ch=='-') f=-1;ch=getchar();}
while(isdigit(ch)) {x=x*10+ch-'0';ch=getchar();}
return x*f;
}
const db eps=1e-6;
int n,m,op[10],p,w[10],res=0;
vector<int> ans[5];
inline int isz(db x){return (-eps<x&&x<eps);}
int isd(db x){return fabs(x-(int)x)>=eps;}
db calc(db a,db b,int c)
{
if(c==1) return a+b;
if(c==2) return a-b;
if(c==3) return a*b;
if(isz(b)) return inf;
return a/b;
}
int cheq()
{
int ret=0,rett=0;db res=0;
if(p==1)
{
db t1=calc(w[1],w[2],op[1]);
if(isz(t1-inf)){ret=0;return ret;}
if(isd(t1)) rett=1;
db t2=calc(t1,w[3],op[2]);
if(isz(t2-inf)){ret=0;return ret;}
if(isd(t2)) rett=1;
res=calc(t2,w[4],op[3]);
if(isz(res-m)) ret=1;
else {ret=0;return ret;}
}
else if(p==2)
{
db t1=calc(w[1],w[2],op[1]);
if(isz(t1-inf)){ret=0;return ret;}
if(isd(t1)) rett=1;
db t2=calc(w[3],w[4],op[3]);
if(isz(t2-inf)){ret=0;return ret;}
if(isd(t2)) rett=1;
res=calc(t1,t2,op[2]);
if(isz(res-m)) ret=1;
else {ret=0;return ret;}
}
else if(p==3)
{
db t1=calc(w[2],w[3],op[2]);
if(isz(t1-inf)){ret=0;return ret;}
if(isd(t1)) rett=1;
db t2=calc(w[1],t1,op[1]);
if(isz(t2-inf)){ret=0;return ret;}
if(isd(t2)) rett=1;
res=calc(t2,w[4],op[3]);
if(isz(res-m)) ret=1;
else {ret=0;return ret;}
}
else if(p==4)
{
db t1=calc(w[2],w[3],op[2]);
if(isz(t1-inf)){ret=0;return ret;}
if(isd(t1)) rett=1;
db t2=calc(t1,w[4],op[3]);
if(isz(t2-inf)){ret=0;return ret;}
if(isd(t2)) rett=1;
res=calc(w[1],t2,op[1]);
if(isz(res-m)) ret=1;
else {ret=0;return ret;}
}
else if(p==5)
{
db t1=calc(w[3],w[4],op[3]);
if(isz(t1-inf)){ret=0;return ret;}
if(isd(t1)) rett=1;
db t2=calc(w[1],w[2],op[1]);
if(isz(t2-inf)){ret=0;return ret;}
if(isd(t2)) rett=1;
res=calc(t1,t2,op[2]);
if(isz(res-m)) ret=1;
else {ret=0;return ret;}
}
else
{
db t1=calc(w[3],w[4],op[3]);
if(isz(t1-inf)){ret=0;return ret;}
if(isd(t1)) rett=1;
db t2=calc(w[2],t1,op[2]);
if(isz(t2-inf)){ret=0;return ret;}
if(isd(t2)) rett=1;
res=calc(w[1],t2,op[1]);
if(isz(res-m)) ret=1;
else {ret=0;return ret;}
}
return ret+rett;
}
void dfs2(int i,int &jud)
{
if(!jud) return;
if(i>n-1)
{
int ok=jud,flg;
for(p=1;p<=6;++p)
{
flg=cheq();
if(flg==1) ok=0;
else if(flg==2&&ok) ok=1;
}
jud=ok;return;
}
rep(j,1,4){op[i]=j;dfs2(i+1,jud);}
}
void dfs(int i,int las)
{
if(i>n)
{
int jud=-1;
do {dfs2(1,jud);}
while(next_permutation(w+1,w+n+1));
if(jud>0) {res++;rep(j,1,n) ans[j].pb(w[j]);}
return;
}
rep(j,las,13) {w[i]=j;dfs(i+1,j);}
return;
}
int main()
{
n=read(),m=read();if(n<=3) return puts("0"),0;
dfs(1,1);printf("%d\n",res);
rep(i,0,res-1) {rep(j,1,n) cout<<ans[j][i]<<" ";puts("");}
}
G
樹套樹 咕了
H
題解寫了3整頁 過於害怕於是棄了
I
\(0\)操作直接差分即可
對於\(1\)操作,先拆成\([l,n]\)和\([r+1,n]\)兩段異或等差數列
容易發現對每一位來說,異或上的數一定是\(\dots11100001111\dots\)的一部分,連續\(2^i\)個\(0/1\)交錯出現
因此在這一位上的所有修改的週期是一樣的,考慮二階差分
對於每個從\(t\)位置開始異或以\(x\)開始的等差數列,可以先將\(x\)加入到一階差分中
然後只需要找到每一位第一個和\(x\)不一樣的位置,每過\(2^i\)之後改變一次,放進二階差分中
最後先將二階差分陣列按週期性整合\(tag\),得到一階差分陣列,再直接求字首和即可
#include<bits/stdc++.h>
#define inf 2139062143
#define ll long long
#define db double
#define ld long double
#define ull unsigned long long
#define MAXN 600100
#define MOD 998244353
#define Fill(a,x) memset(a,x,sizeof(a))
#define rep(i,s,t) for(int i=(s),i##end=(t);i<=i##end;++i)
#define dwn(i,s,t) for(int i=(s),i##end=(t);i>=i##end;--i)
#define ren for(int i=fst[x];i;i=nxt[i])
#define pls(a,b) (a+b)%MOD
#define mns(a,b) (a-(b)+MOD)%MOD
#define mul(a,b) (1LL*(a)*(b))%MOD
#define pii pair<int,int>
#define fi first
#define se second
#define pb push_back
using namespace std;
inline int read()
{
int x=0,f=1;char ch=getchar();
while(!isdigit(ch)) {if(ch=='-') f=-1;ch=getchar();}
while(isdigit(ch)) {x=x*10+ch-'0';ch=getchar();}
return x*f;
}
int n,q,g[MAXN],s[MAXN];
bool tag[MAXN][30];
void work(int x,int w)
{
s[x]^=w;rep(i,0,29)
{
int t=(((w>>i)+1)<<i)-w+x;
if(t<=n) tag[t][i]^=1;
}
}
int main()
{
n=read(),q=read();rep(i,1,n) g[i]=read();int x,a,b;
rep(i,1,q)
{
x=read();
if(!x) {a=read(),b=read(),x=read();s[a]^=x,s[b+1]^=x;}
else {a=read(),b=read(),x=read();work(a,x),work(b+1,x+b-a+1);}
}
rep(i,1,n) rep(j,0,29) if(tag[i][j])
{
s[i]^=(1<<j);
if(i+(1<<j)<=n) tag[i+(1<<j)][j]^=1;
}
rep(i,1,n) {s[i]^=s[i-1];printf("%d%c",g[i]^s[i],i==n?'\n':' ');}
}
J
簽到題,同色三元環並不好計算,考慮計算異色三元環
異色三元環一定有兩個角是異色的,則只需統計有多少個異色角再
對每個點來說,異色角個數即 黑邊\(\times\)白邊
#include<bits/stdc++.h>
#define inf 2139062143
#define ll long long
#define db double
#define ld long double
#define ull unsigned long long
#define MAXN 100100
#define MOD 998244353
#define Fill(a,x) memset(a,x,sizeof(a))
#define rep(i,s,t) for(int i=(s),i##end=(t);i<=i##end;++i)
#define dwn(i,s,t) for(int i=(s),i##end=(t);i>=i##end;--i)
#define ren for(int i=fst[x];i;i=nxt[i])
#define pls(a,b) (a+b)%MOD
#define mns(a,b) (a-b+MOD)%MOD
#define mul(a,b) (1LL*(a)*(b))%MOD
#define pii pair<int,int>
#define fi first
#define se second
#define pb push_back
using namespace std;
namespace GenHelper
{
unsigned z1,z2,z3,z4,b,u;
unsigned get()
{
b=((z1<<6)^z1)>>13;
z1=((z1&4294967294U)<<18)^b;
b=((z2<<2)^z2)>>27;
z2=((z2&4294967288U)<<2)^b;
b=((z3<<13)^z3)>>21;
z3=((z3&4294967280U)<<7)^b;
b=((z4<<3)^z4)>>12;
z4=((z4&4294967168U)<<13)^b;
return (z1^z2^z3^z4);
}
bool read() {
while (!u) u = get();
bool res = u & 1;
u >>= 1; return res;
}
void srand(int x)
{
z1=x;
z2=(~x)^0x233333333U;
z3=x^0x1234598766U;
z4=(~x)+51;
u = 0;
}
}
using namespace GenHelper;
int n,seed,d[8080];
ll ans,res;
int main()
{
cin>>n>>seed;srand(seed);int x;
rep(i,1,n) rep(j,i+1,n) x=read(),d[i]+=x,d[j]+=x;
ans=1LL*n*(n-1)*(n-2)/6;
rep(i,1,n) ans-=1LL*d[i]*(n-1-d[i])/2;
printf("%lld\n",ans);
}