模板之資料結構_學習筆記

再來一波模板整理~

線段樹：

#include<iostream>#include<cstring>#include<cstdio>#include<algorithm>#define L(x) (x<<1)#define R(x) (x<<1|1)#define sz(x) (tree[x].r-tree[x].l+1)using namespace std;typedef long long LL;const int SZ=200000+10;LL a[SZ];struct SGT{    LL l,r,add,sum;}tree[SZ<<2];void update(LL p){    tree[p].sum=tree[R(p)].sum+tree[L(p)].sum;    return;}void spread(LL p){    if(!tree[p].add) return;    tree[L(p)].add+=tree[p].add;    tree[R(p)].add+=tree[p].add;    tree[L(p)].sum+=tree[p].add*sz(L(p));    tree[R(p)].sum+=tree[p].add*sz(R(p));    tree[p].add=0;    update(p);    return;}void build(LL l,LL r,LL p){    tree[p].l=l;tree[p].r=r;    if(l==r)    {        tree[p].sum=a[l];        return;    }    LL mid=(tree[p].l+tree[p].r)>>1;    build(l,mid,L(p));    build(mid+1,r,R(p));    update(p);    return;}void change(LL l,LL r,LL p,LL v){    if(l<=tree[p].l&&tree[p].r<=r)    {        tree[p].add+=v;        tree[p].sum+=v*sz(p);        return;    }    spread(p);    LL mid=(tree[p].l+tree[p].r)>>1;    if(l<=mid) change(l,r,L(p),v);    if(mid<r) change(l,r,R(p),v);    update(p);    return;}LL ask(LL l,LL r,LL p){    LL ans=0;    if(l<=tree[p].l&&tree[p].r<=r) return tree[p].sum;    spread(p);    LL mid=(tree[p].l+tree[p].r)>>1;    if(l<=mid) ans+=ask(l,r,L(p));    if(mid<r) ans+=ask(l,r,R(p));    return ans;}int main(){    int n;    scanf("%d",&n);    for(int i=1;i<=n;i++)        scanf("%lld",&a[i]);    build(1,n,1);    int m;    scanf("%d",&m);    for(int i=1;i<=m;i++)    {        int t;        scanf("%d",&t);        if(t==1)        {            int l,r,s;            scanf("%d%d%d",&l,&r,&s);            change(l,r,1,s);        }        else if(t==2)        {            int l,r;            scanf("%d%d",&l,&r);            printf("%lld\n",ask(l,r,1));        }    }    return 0;}

樹狀數組+差分序列：

#include<iostream>#include<cstdio>#include<cstring>#include<algorithm>#define lowbit(x) (x&(-x))using namespace std;const int MAXN=100000+10;int tree[MAXN],c[MAXN],a[MAXN];int n;void add(int x,int y){    while(x<=n)    {        tree[x]+=y;        x+=lowbit(x);    }}int sum(int x){    int ans=0;    while(x)    {        ans+=tree[x];        x-=lowbit(x);    }    return ans;}int main(){    scanf("%d",&n);    for(int i=1;i<=n;i++)    {        scanf("%d",&a[i]);        c[i]=a[i]-a[i-1];        add(i,c[i]);    }    int q;scanf("%d",&q);    while(q--)    {        int t,l,r,s;        scanf("%d",&t);        if(t==1)        {            scanf("%d%d%d",&l,&r,&s);            add(l,s);            add(r+1,-s);        }        if(t==2)        {            int pos;            scanf("%d",&pos);            printf("%d\n",sum(pos));        }    }    return 0;}

並查集：

#include<iostream>#include<cstdio>using namespace std;const int MAXN=5000+50;int fa[MAXN];int find(int x){    if(fa[x]==x) return x;    else return fa[x]=find(fa[x]);}void merge(int x,int y){    int fx=find(x);    int fy=find(y);    fa[fx]=fy;}int main(){    int n,m,q,a,b;    scanf("%d%d%d",&n,&m,&q);    for(int i=1;i<=n;i++)        fa[i]=i;    for(int i=1;i<=m;i++)    {        scanf("%d%d",&a,&b);        merge(a,b);    }    int x,y;    for(int i=1;i<=q;i++)    {        scanf("%d%d",&x,&y);        if(find(x)==find(y))            puts("Yes");        else            puts("No");    }    return 0;}

單調隊列：

#include<iostream>#include<cstdio>#include<cstring>#include<algorithm>using namespace std;int n,m;int num[1000000+10];int q[1000000+10],que[1000000+10];void init(){    scanf("%d%d",&n,&m);    for(int i=1;i<=n;i++)        scanf("%d",&num[i]);}void up(){    puts("");    int head=1,tail=0;    for(int i=1;i<=n;i++)    {        while(head<=tail&&num[i]>num[q[tail]]) tail--;        q[++tail]=i;        if(i>=m)        {            while(head<=tail&&i-m>=q[head]) head++;            printf("%d ",num[q[head]]);        }    }}void down(){    int head=1,tail=0;    for(int i=1;i<=n;i++)    {        while(head<=tail&&num[i]<num[que[tail]]) tail--;        que[++tail]=i;        if(i>=m)        {            while(head<=tail&&i-m>=que[head]) head++;            printf("%d ",num[que[head]]);        }    }}void work(){    down();    up();}int main(){    init();    work();    return 0;}