Starry

发表于 更新于 分类于 本文字数： 444 阅读时长 ≈ 2 分钟

看错题面，还写挂每个格子对应id的式子

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#include <bits/stdc++.h>
/*
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/hash_policy.hpp>
*/
using namespace std;

const double eps = 1e-10;
const double pi = 3.1415926535897932384626433832795;
const double eln = 2.718281828459045235360287471352;

#define f(i, a, b) for (int i = a; i <= b; i++)
#define scan(x) scanf("%d", &x)
#define mp make_pair
#define pb push_back
#define lowbit(x) (x&(-x))

#define fi first
#define se second
#define SZ(x) int((x).size())
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define summ(a) (accumulate(all(a), 0ll))

typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef vector<int> vi;

using ll=long long;

int n,m,k,ans,tot=1,hd[(int)1e5+9],cur[(int)1e5+9],s,t,dep[(int)1e5+9];
pii dir[4]={{1,0},{0,1},{-1,0},{0,-1}};

struct Edge{
    int to,nxt,v;
}e[(int)2e5+9];
void add(int u,int v,int w){
    e[++tot]={v,hd[u],w},hd[u]=tot;
    e[++tot]={u,hd[v],0},hd[v]=tot;
}

bool bfs(int st,int en){
    for(int i=0;i<=t;++i)dep[i]=0;
    queue<int>q;
    memcpy(cur,hd,sizeof(hd));
    q.push(st);
    dep[st]=1;
    while(!q.empty()){
        auto u=q.front();
        q.pop();
        for(int eg=hd[u];eg;eg=e[eg].nxt){
            if(!dep[e[eg].to]&&e[eg].v>0){
                dep[e[eg].to]=dep[u]+1;
                q.push(e[eg].to);
            }
        }
    }
    return !!dep[en];
}

int dfs(int u,int en,int flow){
    if(u==en)return flow;
    int r=flow;
    for(int eg=cur[u];eg&&r;eg=e[eg].nxt){
        cur[u]=eg;
        if(e[eg].v>0&&dep[e[eg].to]==dep[u]+1){
            int c=dfs(e[eg].to,en,min(r,e[eg].v));
            r-=c;
            e[eg].v-=c,e[eg^1].v+=c;
        }
    }
    return flow-r;
}

int dinic(int st,int en){
    int ret=0;
    while(bfs(st,en)){
        ret+=dfs(st,en,1<<29);
    }
    return ret;
}

inline int id(int x,int y){return (x-1)*m+y;}

signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>m;
    s=n*m+1,t=n*m+2;
    for(int i=1,x;i<=n;++i)for(int j=1;j<=m;++j){
        cin>>x;
        if(x==1)add(s,id(i,j),1<<29);
        else if(x==2)add(id(i,j),t,1<<29);
        for(auto [xx,yy]:dir){
            xx+=i,yy+=j;
            if(xx<=n&&xx>=1&&yy<=m&&yy>=1){
                add(id(i,j),id(xx,yy),1);
            }
        }
    }
    cout<<dinic(s,t);
    return 0;
}

发表于 更新于 分类于 本文字数： 503 阅读时长 ≈ 2 分钟

老是看错题。。。。

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#include <bits/stdc++.h>
/*
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/hash_policy.hpp>
*/
using namespace std;

const double eps = 1e-10;
const double pi = 3.1415926535897932384626433832795;
const double eln = 2.718281828459045235360287471352;

#define f(i, a, b) for (int i = a; i <= b; i++)
#define scan(x) scanf("%d", &x)
#define mp make_pair
#define pb push_back
#define lowbit(x) (x&(-x))

#define fi first
#define se second
#define SZ(x) int((x).size())
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define summ(a) (accumulate(all(a), 0ll))

typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef vector<int> vi;

using ll=long long;

ll n,c[209],a[209],ss,tt,ans;
int hd[(int)1e5+9],cur[(int)1e5+9],tot=1,dep[(int)1e5+9];

struct Edge{
	int to,nxt,v;
}e[(int)5e5+9];
void add(int u,int v,int w){
	e[++tot]={v,hd[u],w},hd[u]=tot;
	e[++tot]={u,hd[v],0ll},hd[v]=tot;
}

vi g[209],dis[209][209];
bitset<209> vis;

void ddfs(int u,int d,int rt){
	vis[u]=1,dis[rt][d].push_back(u);
	for(auto it:g[u]){
		if(!vis[it])ddfs(it,d+1,rt);
	}
}


bool bfs(int st,int en){
	for(int i=0;i<=tt;++i)dep[i]=0;
	queue<int>q;
	memcpy(cur,hd,sizeof(hd));
	q.push(st);
	dep[st]=1;
	while(!q.empty()){
		auto u=q.front();
		q.pop();
		for(int eg=hd[u];eg;eg=e[eg].nxt){
			if(!dep[e[eg].to]&&e[eg].v>0){
				dep[e[eg].to]=dep[u]+1;
				q.push(e[eg].to);
			}
		}
	}
	return !!dep[en];
}

int dfs(int u,int en,int flow){
	if(u==en)return flow;
	int r=flow;
	for(int eg=cur[u];eg&&r;eg=e[eg].nxt){
		cur[u]=eg;
		if(e[eg].v>0&&dep[e[eg].to]==dep[u]+1){
			int c=dfs(e[eg].to,en,min(r,e[eg].v));
			r-=c;
			e[eg].v-=c,e[eg^1].v+=c;
		}
	}
	return flow-r;
}

int dinic(int st,int en){
	int ret=0;
	while(bfs(st,en)){
		ret+=dfs(st,en,0x3f3f3f3f);
	}
	return ret;
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin>>n;
    ss=n*n+n+1,tt=ss+1;
    for(int i=1;i<=n;++i){
    	cin>>c[i];
    	add(i+n*n,tt,c[i]);
    }
    for(int i=1;i<=n;++i)cin>>a[i];
    for(int i=1,x,y;i<n;++i){
    	cin>>x>>y;
    	g[x].push_back(y),g[y].push_back(x);
    }
    for(int i=1;i<=n;++i){
    	vis.reset();
    	ddfs(i,0,i);
    }
    for(int i=1;i<=n;++i){
    	for(int j=1;j<=n;++j){
    		add(ss,(i-1)*n+j,a[j]-a[j-1]);
    		if(j>1)add((i-1)*n+j,(i-1)*n+j-1,0x3f3f3f3f);
    		for(auto it:dis[i][j-1])add((i-1)*n+j,n*n+it,0x3f3f3f3f);
    	}
    }
    ans=n*a[n]-dinic(ss,tt);
    cout<<ans;
    return 0;
}

发表于 更新于 分类于 本文字数： 566 阅读时长 ≈ 2 分钟 
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#include <bits/stdc++.h>
/*
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/hash_policy.hpp>
*/
using namespace std;

const double eps = 1e-10;
const double pi = 3.1415926535897932384626433832795;
const double eln = 2.718281828459045235360287471352;

#define f(i, a, b) for (int i = a; i <= b; i++)
#define scan(x) scanf("%d", &x)
#define mp make_pair
#define pb push_back
#define lowbit(x) (x&(-x))

#define fi first
#define se second
#define SZ(x) int((x).size())
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define summ(a) (accumulate(all(a), 0ll))

typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef vector<int> vi;

using ll=long long;

template <class T> inline T read(const T sample) {
    T x=0; int f=1; char s;
    while((s=getchar())>'9'||s<'0') if(s=='-') f=-1;
    while(s>='0'&&s<='9') x=(x<<1)+(x<<3)+(s^48),s=getchar();
    return x*f;
}

ll n,m;
string s;
int hd[1009],cur[1009],dep[1009],tot=1,ss,tt,ans;
bitset<1009> vis;
struct Edge{
	int to,nxt,v;
}e[(int)2e5+9];
void add(int u,int v,int w){
	e[++tot]={v,hd[u],w},hd[u]=tot;
	e[++tot]={u,hd[v],0},hd[v]=tot;
}

void dfs(int u){
	vis[u]=1;
	for(int eg=hd[u];eg;eg=e[eg].nxt){
		if(!vis[e[eg].to]&&e[eg].v>0)dfs(e[eg].to);
	}
}

bool bfs(int st,int en){
	for(int i=0;i<=n+m+2;++i)dep[i]=0;
	queue<int>q;
	memcpy(cur,hd,sizeof(hd));
	q.push(st);
	dep[st]=1;
	while(!q.empty()){
		auto u=q.front();
		q.pop();
		for(int eg=hd[u];eg;eg=e[eg].nxt){
			if(!dep[e[eg].to]&&e[eg].v>0){
				dep[e[eg].to]=dep[u]+1;
				q.push(e[eg].to);
			}
		}
	}
	return !!dep[en];
}

int dfs(int u,int en,int flow){
	if(u==en)return flow;
	int r=flow;
	for(int eg=cur[u];eg&&r;eg=e[eg].nxt){
		cur[u]=eg;
		if(e[eg].v>0&&dep[e[eg].to]==dep[u]+1){
			int c=dfs(e[eg].to,en,min(r,e[eg].v));
			r-=c;
			e[eg].v-=c,e[eg^1].v+=c;
		}
	}
	return flow-r;
}

int dinic(int st,int en){
	int ret=0;
	while(bfs(st,en)){
		ret+=dfs(st,en,0x3f3f3f3f);
	}
	return ret;
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin>>m>>n;
    ss=n+m+1,tt=ss+1;
    //while(getchar()!='\n');
    getline(cin,s);
    for(int i=1;i<=m;++i){
    	vi v;
    	getline(cin,s);
    	ll x=0,f=1,lst=0;
    	for(auto it:s){
    		if(lst){
    			if(it>='0'&&it<='9')x=(x<<1)+(x<<3)+(it^48),lst=1;
    			else {
    				v.push_back(f*x);
    				x=0,f=1,lst=0;
    			}
    		}else{
    			if(it=='-')f=-1,lst=1;
    			else if(it>='0'&&it<='9')x=(x<<1)+(x<<3)+(it^48),lst=1;
    			else lst=0;
    		}
    	}
    	if(lst)v.push_back(f*x);
    	add(ss,i,v[0]);
    	ans+=v[0];
    	for(int j=1;j<v.size();++j)add(i,m+v[j],0x3f3f3f3f);
    }
	for(int i=1,x;i<=n;++i){
		cin>>x;
		add(m+i,tt,x);
	}

	ans-=dinic(ss,tt);
	dfs(ss);
	f(i,1,m)if(vis[i])cout<<i<<" ";
	cout<<"\n";
	f(i,m+1,n+m)if(vis[i])cout<<i-m<<' ';
	cout<<"\n";
	cout<<ans<<"\n";
    return 0;
}

发表于 更新于 分类于 本文字数： 251 阅读时长 ≈ 1 分钟 
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#include <bits/stdc++.h>
/*
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/hash_policy.hpp>
*/
using namespace std;

const double eps = 1e-10;
const double pi = 3.1415926535897932384626433832795;
const double eln = 2.718281828459045235360287471352;

#define f(i, a, b) for (int i = a; i <= b; i++)
#define scan(x) scanf("%d", &x)
#define mp make_pair
#define pb push_back
#define lowbit(x) (x&(-x))

#define fi first
#define se second
#define SZ(x) int((x).size())
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define summ(a) (accumulate(all(a), 0ll))

typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef vector<int> vi;

using ll=long long;

ll n,m,a[(int)4e5+9],l[(int)4e5+9],r[(int)4e5+9],ans;
bitset<(int)5e5+9> vis;
priority_queue<pair<ll,ll>>q;
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>m;
    f(i,1,n)cin>>a[i];
    if(2*m>n){
    	cout<<"Error!\n";
    	return 0;
    }
    for(int i=1;i<=n;++i)l[i]=(n+i-2)%n+1,r[i]=(n+i)%n+1;
    for(int i=1;i<=n;++i)q.push({a[i],i});
    while(!q.empty()&&m){
    	auto [aa,bb]=q.top();
    	q.pop();
    	if(vis[bb])continue;
    	vis[bb]=vis[l[bb]]=vis[r[bb]]=1,ans+=aa,n+=1,m-=1,a[n]=a[l[bb]]+a[r[bb]]-a[bb];
    	l[n]=l[l[bb]],r[n]=r[r[bb]],r[l[n]]=n,l[r[n]]=n;
    	q.push({a[n],n});
    }
    cout<<ans;
    return 0;
}


发表于 更新于 分类于 本文字数： 249 阅读时长 ≈ 1 分钟

建虚点，注意左右边界要更新

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#include <bits/stdc++.h>
/*
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/hash_policy.hpp>
*/
using namespace std;

const double eps = 1e-10;
const double pi = 3.1415926535897932384626433832795;
const double eln = 2.718281828459045235360287471352;

#define f(i, a, b) for (int i = a; i <= b; i++)
#define scan(x) scanf("%d", &x)
#define mp make_pair
#define pb push_back
#define lowbit(x) (x&(-x))

#define fi first
#define se second
#define SZ(x) int((x).size())
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define summ(a) (accumulate(all(a), 0ll))

typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef vector<int> vi;

using ll=long long;

ll n,k,l[(int)1e6+9],r[(int)1e6+9],ans,a[(int)1e6+9]; 
priority_queue<pair<ll,ll>> q;
bitset<(int)1e6+9> vis;
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>k;
    for(int i=1;i<=n;++i)l[i]=i-1,r[i]=i+1;
    for(ll i=1,x;i<=n;++i){
    	cin>>a[i];
    	q.push({a[i],i});
    }
    while(k&&!q.empty()&&q.top().first>0){
    	auto [aa,bb]=q.top();
    	q.pop();
    	if(vis[bb])continue;
    	vis[bb]=vis[l[bb]]=vis[r[bb]]=1,ans+=aa,n+=1,k-=1,a[n]=a[l[bb]]+a[r[bb]]-a[bb];
    	l[n]=l[l[bb]],r[n]=r[r[bb]],r[l[n]]=n,l[r[n]]=n;
    	q.push({a[n],n});
    }
    cout<<ans;
    return 0;
}
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