-
-
Notifications
You must be signed in to change notification settings - Fork 299
/
483.java
84 lines (70 loc) · 2.25 KB
/
483.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
84
__________________________________________________________________________________________________
sample 1 ms submission
class Solution {
public String smallestGoodBase(String n) {
long num = 0;
for (char c : n.toCharArray()) num = num * 10 + c - '0';
long x = 1;
for (int p = 64; p >= 1; p--) {
if ((x << p) < num) {
long k = helper(num, p);
if (k != -1) return String.valueOf(k);
}
}
return String.valueOf(num - 1);
}
private long helper(long num, int p) {
long l = 1, r = (long)(Math.pow(num, 1.0/p) + 1);
while (l < r) {
long mid = l + (r - l) / 2;
long sum = 0, cur = 1;
for (int i = 0; i <= p; i++) {
sum += cur;
cur *= mid;
}
if (sum == num) return mid;
else if (sum > num) r = mid;
else l = mid + 1;
}
return -1;
}
}
__________________________________________________________________________________________________
sample 35640 kb submission
class Solution {
public String smallestGoodBase(String n) {
long num = 0;
for(char c : n.toCharArray())
num = num * 10 + c - '0';
long x = 1;
int p = 60;
while((x << p) >= num)
p--;
while(p > 0){
long k = helper(num, p);
if(k != -1)
return String.valueOf(k);
p--;
}
return String.valueOf(num - 1);
}
private long helper(long num, int p){
long l = 1, r = (long)(Math.pow(num, 1.0 / p) + 1);
while(l < r){
long mid = l + (r - l) / 2;
long sum = 0, cur = 1;
for(int i = 0; i <= p; i++){
sum += cur;
cur *= mid;
}
if(sum == num)
return mid;
else if(sum > num)
r = mid;
else
l = mid + 1;
}
return -1;
}
}
__________________________________________________________________________________________________