Codeforces Beta Round #90, problem: (C) Education Reform DP

做法：反正a,b之间只有100的长度，之间DP即可啊。

可是，可是一开始dp数组开成了char，WA到死。

#include <iostream>#include <cstring>#include <algorithm>#include <cstdio>#include <utility>#include <vector>#define LL long long#define it set<LL>::iteratorconst int LMT=55;using namespace std;struct cricu{    LL a,b;    int tag,c;    bool operator<(const cricu &x)const    {        return c<x.c;    }}cri[LMT];struct line{    bool wid[LMT<<1];    int len;}dp[LMT][LMT];pair<int,int> pre[LMT][LMT][LMT<<1];pair<int,LL>ans;LL k,sum[LMT][LMT][LMT<<1];int can[LMT];vector<pair<int,LL> >vec;int n,m;int main(){    int p=0;    LL have=0;    int d;    ans=make_pair(-1,0);    cin>>n>>m>>k;    for(int i=1;i<=m;i++)    {      cin>>cri[i].a>>cri[i].b>>cri[i].c;      cri[i].tag=i;    }    sort(cri+1,cri+1+m);    for(int i=1;i<=m;i++)    {        for(int j=1;j<=n;j++)          dp[i][j].len=(int)(cri[i].b-cri[i].a+1);          for(int j=0;j<dp[i][1].len;j++)          dp[i][1].wid[j]=1;        for(int j=0;j<dp[i][1].len;j++)        sum[i][1][j]=cri[i].a+j;    }    for(int i=1;i<=m;i++)    {        if(p<n&&(i==1||cri[i].c>cri[i-1].c))p++;        can[i]=p;        for(int j=2;j<=can[i];j++)          for(int ii=i-1;can[ii]>=j-1&&ii>0;ii--)         {          if(cri[ii].c<cri[i].c)            for(int t=0;t<dp[ii][j-1].len;t++)            if(dp[ii][j-1].wid[t])            {               if((cri[ii].a+t)+k>=cri[i].a&&cri[ii].a+t+k<=cri[i].b)               {                   d=(int)((cri[ii].a+t)+k-cri[i].a);                   dp[i][j].wid[d]|=1;                   if(sum[i][j][d]<sum[ii][j-1][t]+(cri[ii].a+t)+k)                   {                       sum[i][j][d]=sum[ii][j-1][t]+(cri[ii].a+t)+k;                       pre[i][j][d].first=ii;                       pre[i][j][d].second=t;                   }               }               if((cri[ii].a+t)*k>=cri[i].a&&(cri[ii].a+t)*k<=cri[i].b)               {                   d=(int)((cri[ii].a+t)*k-cri[i].a);                   dp[i][j].wid[d]|=1;                   if(sum[i][j][d]<sum[ii][j-1][t]+(cri[ii].a+t)*k)                   {                       sum[i][j][d]=sum[ii][j-1][t]+(cri[ii].a+t)*k;                       pre[i][j][d].first=ii;                       pre[i][j][d].second=t;                   }               }            }         }            for(int t=dp[i][n].len-1;t>=0;t--)            if(dp[i][n].wid[t])            {                if(have<sum[i][n][t])                {                    have=sum[i][n][t];                    ans.second=t;                    ans.first=i;                }            }    }    if(ans.first==-1)printf("NO\n");    else    {        int have=n;        pair<int,LL> x=ans;        printf("YES\n");        while(have)        {            vec.push_back(make_pair(x.first,x.second+cri[x.first].a));            x=pre[x.first][have][x.second];            have--;        }        while(!vec.empty())        {            cout<<cri[vec.back().first].tag<<" "<<vec.back().second<<endl;            vec.pop_back();        }    }    return 0;}