！ HDU chopsticks-dp-(group problem)

Test instructions: A new type of chopsticks: Each pair has three, two short, the length of the difference should be as small as possible, a long, as long as the satisfaction is a pair of the longest on the line. Choose K pair in n chopsticks, ask for short chopsticks in each pair of length difference sum minimum

Analysis:

Group DP model. This question is similar to moving the bedroom, but the problem of each group more than a long chopsticks, so the sort of time from large to small, so that in the time of DP when the long selected into each group, the concrete how to achieve not too much.

Just as there are two ways to implement the grouping model summarized in the dorm, here are two codes. Note Some detail differences in the implementation, as well as initialization.

Combine the two questions to see a deeper understanding.

Code Listing 1:

#include <iostream> #include <algorithm> #include <cstdio> #include <cstring> #define MIN (b) A <b?a:b; #define INF 1000000007using namespace Std;int t,k,n;int dp[5010][1100],a[5100];bool cmp (int i,int j) {return i& Gt;j;} int main () {cin>>t;while (t--) {cin>>k>>n;for (int i=1;i<=n;i++) Cin>>a[i];sort (a+1,a+n+1, CMP); k+=8;for (int i=0;i<=n;i++) for  (int j=1;j<=k;j++)     dp[i][j]=inf;for (int i=0;i<=n;i++) dp[i][0] =0;for (int i=3;i<=n;i++) {for (int j=1;j*3<=i;j++) {    dp[i][j]=min (dp[i-1][j],dp[i-2][j-1]+ (a[i]-a[i-1)) * ( A[I]-A[I-1]));}} Cout<<dp[n][k]<<endl;}}

Code Listing 2:

#include <iostream> #include <algorithm> #include <cstring> #define MIN (b) a<b?a:b;using namespace Std;int t,k,n;int dp[1010][5100],a[5100];bool cmp (int i,int j) {return i>j;} int main () {cin>>t;while (t--) {cin>>k>>n;for (int i=1;i<=n;i++) Cin>>a[i];sort (a+1,a+n+1, CMP), memset (Dp,0,sizeof (DP)), k+=8;for (int i=1;i<=k;i++) {dp[i][3*i]=dp[i-1][3*i-2]+ (a[3*i]-a[3*i-1]) * (a[3*i]- A[3*I-1]); for (int j=3*i+1;j<=n;j++)    dp[i][j]=min (dp[i][j-1],dp[i-1][j-2]+ (a[j]-a[j-1]) * (A[j]-a[j-1]);} Cout<<dp[k][n]<<endl;}}

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！ HDU chopsticks-dp-(group problem)