1342. Enterprise

http://acm.timus.ru/problem.aspx?space=1&num=1342

简单DP

代码：

#include<iostream>

#include<stdio.h>

#include<string.h>

#include<math.h>

#include<algorithm>

#include<vector>

#include<set>

#include<map>

#include<string>

#include<queue>

#include<stack>

#include <iomanip>

using namespace std;

#define LL long long

const int INF=0x3f3f3f3f;

const double FINF=1e12;

const int N=1005;

double ans[N][N];

int k[N];

double p[N],q[N];

int main()

{

    //freopen("data.in","r",stdin);

    int n,m;

    while(cin>>n>>m)

    {

        for(int i=1;i<=n;++i)

        cin>>k[i]>>p[i]>>q[i];

        for(int i=0;i<=n;++i)

        for(int j=0;j<=m;++j)

        if(j==0)

        ans[i][j]=0.0;

        else

        ans[i][j]=FINF;

        for(int i=1;i<=n;++i)

        for(int j=1;j<=m;++j)

        {

            double sum=0.0;

            double t=0.0;

            if(k[i]>1)

            t=(q[i]-p[i])/(k[i]-1);

            for(int l=0;l<=k[i]&&l<=m;++l)

            {

                if(l>0)

                sum+=(p[i]+(l-1)*t);

                ans[i][j]=min(ans[i][j],sum+ans[i-1][j-l]);

            }

        }

        if(ans[n][m]<FINF)

        printf("Minimum possible cost: %.2f\n",ans[n][m]);

        else

        {

            int w;

            for(w=m;w>=0;--w)

            if(ans[n][w]<FINF)

            break;

            printf("Maximum possible amount: %d\n",w);

            printf("Minimum possible cost: %.2f\n",ans[n][w]);

        }

    }

    return 0;

}