Luogu 魔法学院杯-第二弹（萌新的第一法blog）

虽然有点久远  还是放一下吧。

传送门：https://www.luogu.org/contest/show?tid=754

第一题  沉迷游戏，伤感情

#include <queue>
#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;

long long t,n,ans,i,c[],last,now,sum[],s;
deque<long long> q;

inline long long read()
{
    long long ret=,iep=;char ch=getchar();
    while (ch<'' || ch>'') {if (ch=='-') iep=-;ch=getchar();}
    while (ch>=''&&ch<='') {ret=ret*+ch-'';ch=getchar();}
    return ret;
}

int main()
{
    t=read();
    while (t--)
    {
        n=read();ans=;memset(sum,,sizeof sum);
        for (i=;i<=n;i++) s=read(),sum[i]=s+sum[i-];
        q.clear();
        for (i=;i<=n;i++)
        {
            c[i]=read();
            while (!q.empty() && c[i]<=c[q.back()]) q.pop_back();
            q.push_back(i);
        }
        last=;
        while (!q.empty())
        {
            now=q.front();
            q.pop_front();
            ans+=(sum[now]-sum[last])*c[now];
            last=now;
        }
        printf("%lld\n",ans);
    }
}

第二题  精研白学，减智商

#include <cstdio>
#include <iostream>
#include <algorithm>
using namespace std;

int n,m,t,x,y,last,i,k,tot;
double f[][],z,a[];

struct node{
    int x,y;
    double z;
}A[];

struct edge{
    double s[][];
    edge operator *(const edge &x) const
    {
        edge ret;
        for (int i=;i<=n;i++)
            for (int j=;j<=n;j++){
                ret.s[i][j]=;
                for (int k=;k<=n;k++)
                    ret.s[i][j]+=s[i][k] * x.s[k][j];
            }
        return ret;
    }
}mat,map;

inline int read()
{
    int ret=,iep=;char ch=getchar();
    while (ch<'' || ch>'') {if (ch=='-') iep=-;ch=getchar();}
    while (ch>=''&&ch<='') {ret=ret*+ch-'';ch=getchar();}
    return ret;
}

int dfs()
{
    last=;
    for (i=;i<=n;i++) f[i][]=a[i];
    for (i=;i<=n;i++) f[i][(last+)%]=;
    for (i=;i<=tot;i++) f[A[i].y][(last+)%]+=f[A[i].x][last%]*map.s[A[i].y][A[i].x]*1.0;
}

edge ksm(int x)
{
    if (x==) return mat;
    edge ret=ksm(x/);
    ret=ret*ret;
    if (x&) return ret*mat;
    return ret;
}

int doit()
{
    last=;
    for (i=;i<=n;i++) f[i][]=a[i];
    for (k=;k<=t;k++)
    {
        for (i=;i<=n;i++) f[i][(last+)%]=;
        for (i=;i<=tot;i++) f[A[i].y][(last+)%]+=f[A[i].x][last%]*A[i].z*1.0;
        last++;
    }
}

int main()
{
    n=read();m=read();t=read();tot=;
    if (n<)
    {
        for (i=;i<=m;i++)
            tot++,A[tot].x=read(),A[tot].y=read(),cin>>A[tot].z,mat.s[A[tot].y][A[tot].x]+=A[tot].z;
        map=ksm(t);
        for (i=;i<=n;i++) cin>>a[i];
        dfs();last++;
        for (i=;i<n;i++)
            printf("%.6f ",f[i][last%]);
        printf("%.6f\n",f[n][last%]);
    }
    else
    {
        for (i=;i<=m;i++)
            tot++,A[tot].x=read(),A[tot].y=read(),cin>>A[tot].z;
        for (i=;i<=n;i++) cin>>a[i];
        doit();
        for (i=;i<n;i++)
            printf("%.6f ",f[i][last%]);
        printf("%.6f\n",f[n][last%]);
    }
    return ;
}