分糖果问题(上坡和下破问题)

//分糖果问题(上坡和下破问题)
public class CandyProblem{

     //(1)原问题
     public static int Candy1(int[]arr)
     {
          if(arr==null||arr.length==0)
          {
              return 0;
          }
          int index=nextMinIndex1(arr,0);
          int res= rightCands(arr,0,index++);
          int lbase=1;
          int next=0;
          int rcands=0;
          int rbase=0;

          while(index!=arr.length)
          {
               if(arr[index]>arr[index-1])
               {
                    res+=++lbase;
                    index++;
               }else if(arr[index]<arr[index-1])
               {
                   next=nextMinIndex1(arr,index-1);
                   rcands=rightCands(arr,index-1,next++);
                   rbase=next-index+1;
                   res+=rcands+(rbase>lbase?-lbase:-rbase);
                   lbase=1;
                   index=next;
               }else{

                   res+=1;
                   lbase=1;
                   index++;
               }
          }
          return res;
     } 

     public static int nextMinIndex1(int[]arr,int start)
     {
         for(int  i=start;i!=arr.length-1;i++)
         {
              if(arr[i]<=arr[i+1])
              {
                return i;
              }
         }
         return arr.length-1;
     }

     public static int rightCands(int[]arr,int left,int right){

          int n=right-left+1;
          return n+n*(n-1)/2;
     }

     //**********************进阶问题**************************
     public static int candy2(int[] arr) {
        if (arr == null || arr.length == 0) {
            return 0;
        }
        int index = nextMinIndex2(arr, 0);
        int[] data = rightCandsAndBase(arr, 0, index++);
        int res = data[0];
        int lbase = 1;
        int same = 1;
        int next = 0;
        while (index != arr.length) {
            if (arr[index] > arr[index - 1]) {
                res += ++lbase;
                same = 1;
                index++;
            } else if (arr[index] < arr[index - 1]) {
                next = nextMinIndex2(arr, index - 1);
                data = rightCandsAndBase(arr, index - 1, next++);
                if (data[1] <= lbase) {
                    res += data[0] - data[1];
                } else {
                    res += -lbase * same + data[0] - data[1] + data[1] * same;
                }
                index = next;
                lbase = 1;
                same = 1;
            } else {
                res += lbase;
                same++;
                index++;
            }
        }
        return res;
    }

    public static int nextMinIndex2(int[] arr, int start) {
        for (int i = start; i != arr.length - 1; i++) {
            if (arr[i] < arr[i + 1]) {
                return i;
            }
        }
        return arr.length - 1;
    }

    public static int[] rightCandsAndBase(int[] arr, int left, int right) {
        int base = 1;
        int cands = 1;
        for (int i = right - 1; i >= left; i--) {
            if (arr[i] == arr[i + 1]) {
                cands += base;
            } else {
                cands += ++base;
            }
        }
        return new int[] { cands, base };
    }
     public static void main(String[]args)
     { 
         //System.out.println("Hello");
         //原问题
         int[] test1 = { 3, 0, 5, 5, 4, 4, 0 };
         System.out.println(Candy1(test1));

        //进阶问题
        int[] test2 = { 3, 0, 5, 5, 4, 4, 0 };
        System.out.println(candy2(test2));

     }
}