Painter problem (Dynamic programming) __ Dynamic programming

Import java.util.*;

        Painter problem public class painterproblem{//(1) Get the minimum time required to complete all artwork (dynamic programming method) public static int getTime (Int[]arr,int num) { if (arr==null| | arr.length==0| |
        num<1) {throw new RuntimeException ("Input parameter Error!");
        int mintime=0; Only one person's case if (num==1) {for (int i=0;i<arr.length;i++) {Mintime
            +=arr[i];
        return mintime; 
        } int[]sumarr=new Int[arr.length];   Int[]map=new Int[arr.length];
        Generating a dynamic programming array of length n sumarr[0]=arr[0];
        MAP[0]=ARR[0];
              for (int i=1;i<sumarr.length;i++) {sumarr[i]=sumarr[i-1]+arr[i];
        Map[i]=sumarr[i]; for (int i=1;i<num;i++) {for (int j=map.length-1;j>i-1;j--) {i
                   NT Min=integer.max_value; for (int k=i-1;k<j;k++) {int Cur=matH.max (Map[k],sumarr[j]-sumarr[k]);
                   Min=math.min (min,cur);
             } map[j]=min;
    } return map[arr.length-1]; }//(2) optimized dynamic planning public static int Solution2 (int[] arr, int num) {if (arr = null | | arr.length = 0 | | nu
        M < 1) {throw new RuntimeException ("err");
        } int[] Sumarr = new Int[arr.length];
        int[] map = new Int[arr.length];
        Sumarr[0] = arr[0];
        Map[0] = arr[0];
            for (int i = 1; i < sumarr.length i++) {sumarr[i] = Sumarr[i-1] + arr[i];
        Map[i] = Sumarr[i];
        } int[] Cands = new Int[arr.length]; for (int i = 1; i < Num. i++) {for (int j = map.length-1 J > i-1; j--) {int Minpa
                r = Cands[j]; int Maxpar = j = = Map.length-1?
                J:cands[j + 1];
                int min = Integer.max_value; for (int k = mInpar; K < Maxpar + 1;
                    k++) {int cur = Math.max (map[k], sumarr[j]-sumarr[k]);
                        if (cur <= min) {min = cur;
                    CANDS[J] = k;
            } map[j] = min;
    } return map[arr.length-1]; }//(3) The optimal solution public static int Solution3 (int[] arr, int num) {if (arr = null | | arr.length = 0 | | | Lt
        1) {throw new RuntimeException ("err");
            } if (Arr.length < num) {int max = Integer.min_value;
            for (int i = 0; I!= arr.length i++) {max = Math.max (max, arr[i]);
        return to Max;
            else {int minsum = 0;
            int maxsum = 0;
            for (int i = 0; i < arr.length i++) {maxsum + = Arr[i]; while (Minsum!= maxSum-1) {int mid = (minsUm + maxsum)/2;
                if (Getneednum (arr, mid) > num) {minsum = mid;
                else {maxsum = mid;
        } return maxsum;
        } public static int getneednum (int[] arr, int lim) {int res = 1;
        int stepsum = 0;
            for (int i = 0; I!= arr.length. i++) {if (Arr[i] > Lim) {return integer.max_value;
            } Stepsum + = Arr[i];
                if (Stepsum > Lim) {res++;
            Stepsum = Arr[i];
    } return res;
        }//Get random array public static int[] Generaterandomarray (int length) {int[] result = new Int[length];
        for (int i = 0; I!= result.length i++) {result[i] = (int) (Math.random () * 10) + 1;
    return result; }//print array public static void PrintArray (int[] arr) {for (int i = 0; I!= aRr.length;
        i++) {System.out.print (Arr[i] + "");
    } System.out.println ();
       public static void Main (String[]args) {//system.out.println ("Hello"); int[]arr2={1,1,3,3,4};        Total number of works int num=2;

        The total number of painter System.out.println (GetTime (arr2,num));
        int[] arr = Generaterandomarray (300);
        int[]arr={1,1,3,3,4};
        int painternum = 2;
        System.out.println (Solution2 (arr, painternum));

        System.out.println (Solution3 (arr, painternum));
        arr = Generaterandomarray (1000000);
        Painternum = 10000;
        Long start = System.currenttimemillis ();
        System.out.println (Solution3 (arr, painternum));
        Long end = System.currenttimemillis ();
    System.out.println ("Cost Time:" + (End-start) + "MS"); }
}