高一下三調2

_君の名は發表於2024-05-13

T1攻擊裝置

題目

image

腦癱了,考場上連邊時 \((i-1)*n+j\) 寫成 \(i*n+j\),連邊直接錯位

點選檢視程式碼
#include<bits/stdc++.h>
const int maxn=4e4+10;
using namespace std; 
int n,head[maxn<<3],nxt[maxn<<4],to[maxn<<4],vis[maxn],match[maxn],tot;
int a[500][500],sum,ans;
string s[300];
void add(int x,int y)
{
	to[++tot]=y;
	nxt[tot]=head[x];
	head[x]=tot;
}
bool dfs(int u)
{
	for(int i=head[u];i;i=nxt[i])
	{
		int y=to[i];
		if(vis[y])continue;
		vis[y]=1;
		if(!match[y]||dfs(match[y]))
		{
			match[y]=u;
			return 1;
		}
	}
	return 0;
}
int main()
{
	freopen("attack.in","r",stdin);
	freopen("attack.out","w",stdout);
	scanf("%d",&n);
	for(int i=1;i<=n;i++)
	{
		cin>>s[i];
		for(int j=0;j<n;j++)
		{
			if(s[i][j]=='0')a[i][j+1]=1,sum++;
		}
	}		
	for(int i=1;i<=n;i++)
	{
		for(int j=1;j<=n;j++)
		{
			if(a[i][j]==1)
			{
				if(a[i-2][j-1]==1)add((i-1)*n+j,(i-3)*n+j-1);
				if(a[i-1][j-2]==1)add((i-1)*n+j,(i-2)*n+j-2);
				if(a[i-2][j+1]==1)add((i-1)*n+j,(i-3)*n+j+1);
				if(a[i-1][j+2]==1)add((i-1)*n+j,(i-2)*n+j+2);
				if(a[i+2][j-1]==1)add((i-1)*n+j,(i+1)*n+j-1);
				if(a[i+1][j-2]==1)add((i-1)*n+j,(i)*n+j-2);
				if(a[i+2][j+1]==1)add((i-1)*n+j,(i+1)*n+j+1);
				if(a[i+1][j+2]==1)add((i-1)*n+j,(i)*n+j+2);
			}
		}
	}
	for(int i=1;i<=n*n;i++)
	{
		memset(vis,0,sizeof(vis));
		if(dfs(i))ans++;
	}
	printf("%d\n",sum-ans/2);
	
	return 0;
}
/*
3
010
000
100
*/

T2迴圈

題目

image

水題

點選檢視程式碼
#include<bits/stdc++.h>
const int maxn=1e3+10;
const int mod=100;
int x,vis[maxn];
int main()
{
	freopen("number.in","r",stdin);
	freopen("number.out","w",stdout);
	scanf("%d",&x);
	x%=100;
	int flag=1,ans=1;
	while(flag)
	{
		ans=ans*x%100;
		printf("%d ",ans);
		if(vis[ans])flag=0;
		vis[ans]=1;
	}
	
	return 0;
}

T3漫步

題目

image

也是水題,但我想複雜了,打了個貪心的暴力,T倆點

貪心——80pts
#include<bits/stdc++.h>
const int maxn=1e5+10;
using namespace std;
int n,st[maxn],ans,rs,minn=1e10;
struct node{int x,v;}m[maxn];
bool cmp(node a,node b)
{
	return a.x<b.x;
}
int main()
{
	freopen("jog.in","r",stdin);
	freopen("jog.out","w",stdout);
	scanf("%d",&n);
	for(register int i=1;i<=n;i++)
	{
		scanf("%lld%lld",&m[i].x,&m[i].v);	
		minn=min(minn,m[i].v);
	}
	sort(m+1,m+n+1,cmp);
	for(register int i=1;i<=n;i++)
	{
		if(m[i].v==minn)st[++rs]=i;
	}
	ans+=rs;
	int end=st[rs];
	while(minn!=m[n].v&&minn!=1e10)
	{
		minn=1e10;
		memset(st,0,sizeof st);
		rs=0;
		for(register int i=end+1;i<=n;i++)
		{
			minn=min(minn,m[i].v);
		}
		for(register int i=end+1;i<=n;i++)
		{
			if(m[i].v==minn)st[++rs]=i;
		}
		sort(st+1,st+1+rs);
		end=st[rs];
		ans+=rs;
		if(end==n)break;	
	}
	printf("%d\n",ans);
	return 0;
}
/*
5
0 1
1 2
2 3
3 2
6 1
*/
正解
#include<bits/stdc++.h>
#define int long long
const int maxn=1e5+10;
using namespace std;
int n,st[maxn],ans,rs,minn=1e10;
struct node{int x,v;}m[maxn];
bool cmp(node a,node b)
{
	return a.x<b.x;
}
signed main()
{
	freopen("jog.in","r",stdin);
	freopen("jog.out","w",stdout);
	scanf("%lld",&n);
	ans=n;
	for(int i=1;i<=n;i++)
	{
		scanf("%lld%lld",&m[i].x,&m[i].v);	
	}
	sort(m+1,m+n+1,cmp);
	for(int i=n-1;i>=1;i--)
	{
		if(m[i].v>m[i+1].v)ans--,m[i].v=m[i+1].v;
	}
	printf("%d\n",ans);
	return 0;
}
/*
5
0 1
1 2
2 3
3 2
6 1
*/

T4穿越

題目

image

image

當時以為是個搜尋,也確實是個搜尋,但沒打出來,騙了40pts走了

點選檢視程式碼
#include<bits/stdc++.h>
#define fi first
#define se second
const int maxn=1e5+10;
using namespace std;
int n,m,a[400][400],aa,yu[400][400],p,x,y,b,z,h,lsx;
typedef pair<int,int> pii;
vector<pii>q[400][400],ch;
queue<pair<pii,int> >qq;
bool vis[400][400];

void bfs(int x,int y,int t)
{
//	cout<<"!"<<endl;
	if(x<=0||x>n||y<=0||y>m||vis[x][y]==1||a[x][y]==1||t>=yu[x][y])return;
	if(a[x][y]!=2)
	{
		qq.push({{x,y},t});
		vis[x][y]=1;
		if(x==n&&y==m)
		{
			printf("%d\n",t);
			exit(0); 
		}
	}
	else
	{
		for(auto i:q[x][y])
		{
			if(i.fi<=t&&i.se>=t)return;
		}
		qq.push({{x,y},t});
		vis[x][y]=1;
		return;
	}
} 


int main()
{
	freopen("cross.in","r",stdin);
	freopen("cross.out","w",stdout);
	scanf("%d%d",&n,&m);
	memset(yu,0x7f7f7f,sizeof yu);
	for(int i=1;i<=n;i++)
		for(int j=1;j<=m;j++)
		{
			
			scanf("%d",&a[i][j]);
			if(a[i][j]==3)ch.push_back({i,j});
		}	
	scanf("%d",&aa);
	for(int i=1;i<=aa;i++)
	{
		scanf("%d",&lsx);
		scanf("%d",&p);
		for(int j=1;j<=p;j++)
			scanf("%d%d",&x,&y),yu[x][y]=min(lsx,yu[x][y]);
	}
	scanf("%d",&b);
	for(int i=1;i<=b;i++)scanf("%d%d%d%d",&x,&y,&z,&h),q[z][h].push_back({x,y});
	if(a==0&&b==0)printf("%d",n+m-2),exit(0);
	qq.push({{1,1},0}); 
	vis[1][1]=1;
	while(1)
	{
		pii k=qq.front().fi;
		int x=k.fi,y=k.se,t=qq.front().se;
		qq.pop();
		vis[x][y]=0;
		bfs(x+1,y,t+1);bfs(x-1,y,t+1);bfs(x,y+1,t+1);bfs(x,y-1,t+1);bfs(x,y,t+1);
		if(a[x][y]==3)
		{
			for(auto i:ch)bfs(i.fi,i.se,t+2);
		}
	}
	
	return 0;	
} 
/*
3 3
0 1 0
2 0 1
3 2 0
2 
2 1 3 1 
1 1 1 3
1
2 4 2 1
*/

T5結隊

題目

image

image

早上吃飯時還在說會不會考並查集,說中了,但當時卻沒想到。。。

點選檢視程式碼
#include<bits/stdc++.h>
const int maxn=1e5+10;
using namespace std;
int A,B,P,zs[maxn],cnt,ans,v[maxn],fa[maxn];
bool vis[maxn];
int find(int x){return fa[x]==x?x:fa[x]=find(fa[x]);}
void pre()
{
	for(int i=2;i<=sqrt(B);i++)
	{
		if(!vis[i])
		{
			for(int j=2;j*i<=B;j++)
				vis[j*i]=1;
		}
	}
}
int main()
{
	freopen("merge.in","r",stdin);
	freopen("merge.out","w",stdout);
	scanf("%d%d%d",&A,&B,&P);
	pre();
	for(int i=P;i<=B;i++)
		if(!vis[i])zs[++cnt]=i,fa[i]=i;
	for(int i=1;i<=cnt;i++)
	{
		for(int j=1;j*zs[i]<=B;j++)
		{
			int x=j*zs[i];
			if(x<A)continue;
			if(fa[x]&&find(x)!=x)fa[find(x)]=zs[i];
			if(fa[x]==0)fa[x]=zs[i];
		}
	}
	for(int i=A;i<=B;i++)
	{
		int x=find(i);
		if(!v[x]&&x)ans++,v[x]=1;
		if(x==0)ans++; 
	}
	printf("%d\n",ans);
	
	return 0;
}

相關文章