uva147 – Dollars—-沒看懂的做法？

我的方法：

#include<cstdlib>#include<iostream>#include<cstdio>#include<cmath>#include<set>#include<cstring>#include <algorithm>#define inf 0x7fffffff#define N 6005#define MIN 1e-11#define M 100#define LL long longusing namespace std;int n,k,h,t,m;long long a[N];int my[20]={0,1,2,4,10,20,40,100,200,400,1000,2000};int main(){#ifndef ONLINE_JUDGE    freopen("ex.in","r",stdin);#endif//    scanf("%d%*c%*c",&t);    double temp;    while(scanf("%lf",&temp)&&temp!=0.00)    {        printf("%6.2lf",temp);        memset(a,0,sizeof(a));//        n=temp*100;//不正確！！        n=floor(temp*100+0.5);//精度問題        n/=5;        for(int i=1;i<12;i++)        {            a[my[i]]++;            for(int j=my[i]+1;j<=n;j++)            {                a[j]+=a[j-my[i]];            }        }        printf("%17lld\n",a[n]);    }    return 0;}

別人的做法：（沒看懂啊！！！！）

#include<iostream>#include<cstring>#include<algorithm>#include<cstdio>#include<fstream>using namespace std;long long dollar[12]= {0,1,2,4,10,20,40,100,200,400,1000,2000};long long m[6005][12];long long value;long long dp(long long v,long long k){    if(m[v][k]!=-1)return m[v][k];    m[v][k]=0;    for(long long i=k; i<12; i++)    {        if(v>=dollar[i])        {            m[v][k]+=dp(v-dollar[i],i);        }    }    return m[v][k];}int main(){// freopen("test.txt","r",stdin);#ifndef ONLINE_JUDGE    freopen("ex.in","r",stdin);#endif    double a;    memset(m,-1,sizeof(m));    for(long long i=0; i<12; i++)m[0][i]=1;    while(cin>>a)    {        value=(long long)((a*100.0+0.5)/5);        if(!value)break;        long long re=dp(value,1);        printf("%6.2lf%17lld\n",a,re);    }    return 0;}