1
我是C++新手。有人可以将此算法转换为C++代码。我无法完全理解它,谢谢。动态规划 - 活动选择
我能够使用表格矩阵解决纸面上的问题,并且我理解它的分治策略,但是在将s和f数组传递给DP函数后难以实现算法。
for i =1 to n
do m[i] = max(m[i-1], 1+ m [BINARY-SEARCH(f, s[i])])
We have P(i] = 1 if activity i is in optimal selection, and P[i] = 0
otherwise
i = n
while i > 0
do if m[i] = m[i-1]
then P[i] = 0
i = i - 1
else
i = BINARY-SEARCH (f, s[i])
P[i] = 1
到目前为止,我已经能够用贪心算法来做到这一点,
void MaxActGreedy(int s[], int f[], int n)
{
cout<<"\n Entering Greedy Programming Function \n";
clock_t startTime = clock();
cout<<" Greedy Solution (Index no.) :";
int i;
int j;
i=0;
cout<<i;
for(j=1; j<n; j++)
{
if (s[j]>=f[i])
{
cout<<j;
i=j;
}
}
clock_t endTime= clock();
endTime = endTime - startTime;
float timeinSeconds = endTime/(float) CLOCKS_PER_SEC;
cout<<"\n Greedy Time: ";
cout<<timeinSeconds;
cout<<" Seconds";
}
void Dynamic(int s[],int f[],int n)
{
int m[]={0};
for(int i=0; i<n; i++)
{
}
}
int main()
{
int s[]={1,3,0,5,3,5,6,8,8,2,12};//Start Time Si
int f[]={4,5,6,7,8,9,10,11,12,13,14};//Finish Times fi (sorted)
int n = sizeof(s)/sizeof(s[0]);
MaxActGreedy(s,f,n);
// MaxActDP(s,f,n);
Dynamic(s,f,n);
return 0;
}
了解算法的作用,然后用_any_语言实现它会简单得多。 – 2013-03-22 09:13:07
“但实施困难..”显示你的困难。 – qPCR4vir 2013-03-22 09:29:14
@ qPCR4vir我在我的问题中添加了代码。 – 2013-03-22 09:32:01