-
-
Notifications
You must be signed in to change notification settings - Fork 299
/
410.java
83 lines (75 loc) · 2.46 KB
/
410.java
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
__________________________________________________________________________________________________
sample 0 ms submission
class Solution {
public int splitArray(int[] nums, int m) {
if(nums == null || nums.length == 0 || m == 0) {
return 0;
}
long upperBound = 0L;
for(int num : nums) {
upperBound += num;
}
long lowerBound = upperBound / m;
while(lowerBound + 1 < upperBound) {
long mid = (lowerBound + upperBound) / 2;
if(isSplitable(nums, mid, m)) {
upperBound = mid;
} else {
lowerBound = mid;
}
}
if(isSplitable(nums, lowerBound, m)) {
return (int) lowerBound;
} else {
return (int) upperBound;
}
}
//split array using subSum, when the tmp sum is just bigger than subSum, cut it there
private boolean isSplitable(int[] nums, long subSum, int m) {
long tmpSum = 0;
int subArrayLength = 0;
int subArrays = 0;
for(int num : nums) {
// if(subArrays == m) {
// return false;
// }
if(num > subSum) {
return false;
}
if(tmpSum + num > subSum) {
subArrays++;
subArrayLength = 0;
tmpSum = 0;
}
tmpSum += num;
subArrayLength++;
}
if (subArrays < m) {
return true;
}
return false;
}
}
__________________________________________________________________________________________________
sample 33272 kb submission
class Solution {
public int splitArray(int[] nums, int m) {
int low = Arrays.stream(nums).max().orElse(-1);
int high = Arrays.stream(nums).sum();
while (low<high) {
int maxAllowedSum = low + (high-low)/2;
int numOfSubArrays = 1;
for (int i=0, sum=0; i<nums.length; i++) {
sum+=nums[i];
if (sum>maxAllowedSum) {
numOfSubArrays++;
sum = nums[i];
}
}
if (numOfSubArrays>m) low = maxAllowedSum+1;
else high = maxAllowedSum;
}
return low;
}
}
__________________________________________________________________________________________________