板子

不定期更。

数论

const int pri[12]={2,3,5,7,11,13,17,19,23,29,31,37};
ll ksc(ll x,ll y,ll mod){
    ll tmp=x*y-(ll)((ld)x/mod*y+0.5)*mod;
    return tmp<0?tmp+mod:tmp;
}
ll ksm(ll x,ll p,ll mod){
    ll ret=1;
    for (;p;p>>=1,x=ksc(x,x,mod)) if (p&1) ret=ksc(ret,x,mod);
    return ret;
}
bool MR(ll n){
    if (n<=1) return 0;
    rep (i,0,11) if (n==pri[i]) return 1;
    ll d=n-1; int tmp=0;
    while (!(d&1)) d>>=1,tmp++;
    rep (i,0,11){
        ll x=ksm(pri[i],d,n),p=x;
        rep (t,1,tmp){
            x=ksc(x,x,n);
            if (x==1 && p!=1 && p!=n-1) return 0;
            p=x;
        }
        if (x!=1) return 0;
    }
    return 1;
}

vector<ll> V;
namespace Rho{
    const int pri[12]={2,3,5,7,11,13,17,19,23,29,31,37};
    ull Rd;
    ll Rand(ll mod){return (Rd+=4179340454199820289ll)%mod;}
    ll ksc(ll x,ll y,ll mod){
        ll tmp=x*y-(ll)((ld)x/mod*y+0.5)*mod;
        return tmp<0?tmp+mod:tmp;
    }
    ll ksm(ll x,ll p,ll mod){
        ll ret=1;
        for (;p;p>>=1,x=ksc(x,x,mod)) if (p&1) ret=ksc(ret,x,mod);
        return ret;
    }
    bool MR(ll n){
        if (n<=1) return 0;
        rep (i,0,11) if (n==pri[i]) return 1;
        ll d=n-1; int tmp=0;
        while (!(d&1)) d>>=1,tmp++;
        rep (i,0,11){
            ll x=ksm(pri[i],d,n),p=x;
            rep (t,1,tmp){
                x=ksc(x,x,n);
                if (x==1 && p!=1 && p!=n-1) return 0;
                p=x;
            }
            if (x!=1) return 0;
        }
        return 1;
    }
    ll f(ll x,ll c,ll mod){return (ksc(x,x,mod)+c)%mod;}
    ll gcd(ll a,ll b){return !b?a:gcd(b,a%b);}
    ll get(ll c,ll n){
        ll x=Rand(n),y=f(x,c,n),p=n;
        while (x!=y&&(p==n||p==1)){
            p=gcd(n,x>y?x-y:y-x);
            x=f(x,c,n); y=f(f(y,c,n),c,n);
        }
        return p;
    }
    void work(ll n){
        if (n<=1) return;
        if (MR(n)){V.push_back(n); return;}
        while (1){
            ll tmp=get(Rand(n-1)+1,n);
            if (tmp!=n&&tmp!=1){work(tmp); work(n/tmp); return;}
        }
    }
}

字符串

int n,all,rk[N],tp[N],t[N],sa[N],h[N],lg[N],mi[N][23]; char s[N];
void js_sort(){
    rep (i,1,all) t[i]=0;
    rep (i,1,n) t[rk[tp[i]]]++;
    rep (i,1,all) t[i]+=t[i-1];
    for (int i=n;i;i--) sa[t[rk[tp[i]]]--]=tp[i];
}
void get_sa(){
    rep (i,1,n) rk[i]=s[i],tp[i]=i;
    all=127; js_sort(); int w=1; all=1;
    while (all<n){
        int k=0;
        rep (i,n-w+1,n) tp[++k]=i;
        rep (i,1,n) if (sa[i]>w) tp[++k]=sa[i]-w;
        js_sort();
        rep (i,1,n) tp[i]=rk[i];
        rk[sa[all=1]]=1;
        rep (i,2,n) rk[sa[i]]=(tp[sa[i]]==tp[sa[i-1]]&&tp[sa[i]+w]==tp[sa[i-1]+w])?all:++all;
        w<<=1;
    }
    int k=0;
    rep (i,1,n){
        if (k) k--; int j=sa[rk[i]-1];
        for (;i+k<=n&&j+k<=n&&s[i+k]==s[j+k];k++);
        h[rk[i]]=k;
    }
}
void st_init(){
    rep (i,1,n-1) mi[i][0]=h[i+1],lg[i]=i==1?0:lg[i>>1]+1;
    rep (j,1,18)
        for (int i=2;i+(1<<j-1)<n;i++)
            mi[i][j]=min(mi[i][j-1],mi[i+(1<<j-1)][j-1]);
}
int lcp(int x,int y){
    if (x==y) return n-x+1;
    x=rk[x],y=rk[y];
    if (x>y) swap(x,y); y--;
    int t=lg[y-x+1];
    return min(mi[x][t],mi[y-(1<<t)+1][t]);
}

//n=strlen(s+1)
int n,k,las,tot,ch[N][26],fa[N],len[N],sz[N],t[N],q[N]; char s[N];
void init(){
    las=tot=1;
}
void extend(int c){
    int p=las,np=las=++tot,q,nq; len[np]=len[p]+1; sz[np]=1;
    for (;p&&!ch[p][c];p=fa[p]) ch[p][c]=np;
    if (!p){fa[np]=1; return;}
    q=ch[p][c];
    if (len[q]==len[p]+1) fa[np]=q;
    else{
        nq=++tot; len[nq]=len[p]+1;
        memcpy(ch[nq],ch[q],sizeof(ch[q]));
        fa[nq]=fa[q]; fa[q]=fa[np]=nq;
        for (;p&&ch[p][c]==q;p=fa[p]) ch[p][c]=nq;
    }
}
void js_sort(){//基数排序
    rep (i,1,n) t[i]=0;
    rep (i,1,tot) t[len[i]]++;
    rep (i,1,n) t[i]+=t[i-1];
    rep (i,1,tot) q[t[len[i]]--]=i;
}
void get_right(){//计算right集合大小
    for (int i=tot;i;i--){
        int x=q[i];
        sz[fa[x]]+=sz[x];
    }
}

int n,tot,las,ch[N][26],fa[N],len[N]; char s[N];
int get_node(int l){
    rep (i,0,25) ch[tot][i]=0;
    len[tot]=l; return tot++;
}
int get_fail(int i,int x){
    while (s[i-len[x]-1]!=s[i]) x=fa[x];
    return x;
}
void init(){
    las=tot=0;
    get_node(0); get_node(-1);
    fa[0]=1;
}
void extend(int i,int c){
    int x=get_fail(i,las),y;
    if (!ch[x][c]){
        y=get_node(len[x]+2);
        fa[y]=ch[get_fail(i,fa[x])][c];
        ch[x][c]=y;
    }
    las=ch[x][c];
}

二分图

const int N=512;
int n1,n2,m,a[N][N],match[N],vis[N],ans;

bool dfs(int u){
    rep (v,1,n2) if (a[u][v]&&!vis[v]){
        vis[v]=1;
        if (!match[v]||dfs(match[v])) return match[v]=u,1;
    }
    return 0;
}

int main(){
// Init
    rep (i,1,n1){
        memset(vis,0,(n2+1)<<2);
        if (dfs(i)) ans++;
    }

    return 0;
}

const int N=410;
const ll inf=1e15+1;
int n,n1,n2,m,sx[N],sy[N],match[N],L[N],R[N]; ll lx[N],ly[N],w[N][N],val[N];

bool dfs(int u){
    sx[u]=1;
    rep (v,1,n) if (!sy[v]){
        ll tmp=lx[u]+ly[v]-w[u][v];
        if (tmp==0){
            sy[v]=1,R[v]=u,L[match[v]]=v;
            if (!match[v]||dfs(match[v])) return match[v]=u,1;
        } else if (tmp<val[v]) R[v]=u,val[v]=tmp;
    }
    return 0;
}

void km(){
    rep (i,1,n){
        lx[i]=-inf,ly[i]=match[i]=0;
        rep (j,1,n) lx[i]=max(lx[i],w[i][j]);
    }
    rep (x,1,n){
        rep (i,1,n) val[i]=inf,sx[i]=sy[i]=L[i]=R[i]=0;
        int u,v=0;
        for (u=x;u&&!dfs(u);L[u=match[v]]=v){
            ll dlt=inf;
            rep (i,1,n) if (!sy[i]&&val[i]<dlt) dlt=val[v=i];
            rep (i,1,n){
                if (sx[i]) lx[i]-=dlt;
                if (sy[i]) ly[i]+=dlt; else val[i]-=dlt;
            }
            sy[v]=1;
        }
        while (u!=x) u=L[u],match[u]=R[u],u=R[u];
    }
}