Lintcode: Wood Cut
Given n pieces of wood with length L[i] (integer array). Cut them into small pieces to guarantee you could have equal or more than k pieces with the same length. What is the longest length you can get from the n pieces of wood? Given L & k, return the maximum length of the small pieces. Have you met this question in a real interview? Yes Example For L=[232, 124, 456], k=7, return 114. Note You couldn't cut wood into float length. Challenge O(n log Len), where Len is the longest length of the wood.
注意是在[1,max(L)]里面找
1 public class Solution { 2 /** 3 *@param L: Given n pieces of wood with length L[i] 4 *@param k: An integer 5 *return: The maximum length of the small pieces. 6 */ 7 public int woodCut(int[] L, int k) { 8 // write your code here 9 if (L==null || L.length==0 || k<=0) return 0; 10 Arrays.sort(L); 11 int l=1, r=L[L.length-1]; 12 while (l <= r) { 13 int m = l+(r-l)/2; 14 if (calc(L, m)>=k) l=m+1; 15 else r=m-1; 16 } 17 return r; 18 } 19 20 public int calc(int[] L, int len) { 21 int res = 0; 22 for (int i=0; i<L.length; i++) { 23 res += L[i]/len; 24 } 25 return res; 26 } 27 }