清北考前刷题day4下午好

/*
辗转相除，每次计算多出现了几个数。
*/
#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>

#define ll long long

using namespace std;
ll a1,a2,a3,a4,ans;

inline ll read()
{
    ll x=,f=;char c=getchar();
    while(c>''||c<''){if(c=='-')f=-;c=getchar();}
    while(c>=''&&c<=''){x=x*+c-'';c=getchar();}
    return x*f;
}

ll gcd(ll a,ll b)
{
    if(!b) return a;
    ans+=ceil(a/b);
    return gcd(b,a%b);
}

int main()
{
    freopen("seq.in","r",stdin);
    freopen("seq.out","w",stdout);
    ll tmp;
    a1=read();a2=read();
    if(a1<a2) a1^=a2,a2^=a1,a1^=a2;
    ll g=gcd(a1,a2);
    printf("%I64d\n",ans+);
    return ;
}

#include<bits/stdc++.h>
#define N 1010
#define M 40010
using namespace std;
int front[N],cap[M],to[M],nextt[M],dis[N],mx,mn,ans,tot,u,v,w,n,m,now,t;
int siz[];
int sum[];
bool inque[N];
inline void in(int &x)
{
    x=;
    char ch=getchar();
    while(!isdigit(ch)) ch=getchar();
    while(isdigit(ch))
    {
        x=x*+ch-'';
        ch=getchar();
    }
}
inline void add(int u,int v,int w)
{
    to[++tot]=v;
    nextt[tot]=front[u];
    front[u]=tot;
    cap[tot]=w;
    to[++tot]=u;
    nextt[tot]=front[v];
    front[v]=tot;
    cap[tot]=w;
}
queue<int>q;
void spfa(int src)
{
    mx=;
    mn=0x3f3f3f3f;
    memset(dis,-,sizeof(dis));
    memset(inque,,sizeof(inque));
    memset(siz,,sizeof(siz));
    dis[src]=0x3f3f3f3f;
    q.push(src);
    while(!q.empty())
    {
        now=q.front();
        q.pop();
        inque[now]=;
        for(int i=front[now]; i; i=nextt[i])
        {
            t=to[i];
            int val=min(dis[now],cap[i]);
            if(dis[t]<val)
            {
                siz[val]++;
                if(dis[t]!=-) siz[dis[t]]--;
                dis[t]=val;
                if(!inque[t])
                {
                    inque[t]=;
                    q.push(t);
                }
            }
        }
    }
    for(int i=; i>=; i--) sum[i]=sum[i+]+siz[i];
    for(int i=; i<=; i++)
    {
        ans+=(sum[i]-sum[i+])*(sum[i]-sum[i+]);
    }
    ans+=sum[]*sum[];

}
int main()
{
    freopen("car.in","r",stdin);
    freopen("car.out","w",stdout);
    in(n);
    in(m);
    for(int i=; i<=m; i++)
    {
        in(u);in(v);in(w);
        add(u,v,w);
    }
    for(int i=; i<=n; i++)
    {
        ans=;
        spfa(i);
        printf("%d ",ans);
    }
}

30暴力spfa

取数

/*
30暴力dp
*/
#include<iostream>
#include<cstdio>
#include<cstring>

#define N 3001
#define ll long long

using namespace std;
int n,m,k,cnt;
ll ans;
ll f[N][N],a[N];

inline int read()
{
    int x=,f=;char c=getchar();
    while(c>''||c<''){if(c=='-')f=-;c=getchar();}
    while(c>=''&&c<=''){x=x*+c-'';c=getchar();}
    return x*f;
}

int main()
{
    n=read();m=read();k=read();
    memset(f,,sizeof f);ans=0x3f3f3f3f3f;
    for(int i=;i<=n;i++) a[i]=read();
    for(int i=;i<=n;i++) f[i][]=min(f[i-][],a[i]);
    for(int i=m;i<=n;i++)
      for(int j=;j<=k;j++)
          f[i][j]=min(f[i][j],min(f[i-][j],f[i-m][j-]+a[i]));
    for(int i=k;i<=n;i++) ans=min(ans,f[i][k]);
    printf("%I64d\n",ans);
}