blob: 3855d57ac2489d5de6de06e37115e12219262987 (
plain)
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
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
|
#pragma once
#include <string>
//Fast to int to string
//Source: http://stackoverflow.com/a/4351484/192001
//Modified version to pad zeros according to padding arg
namespace spdlog {
namespace details {
const char digit_pairs[201] = {
"00010203040506070809"
"10111213141516171819"
"20212223242526272829"
"30313233343536373839"
"40414243444546474849"
"50515253545556575859"
"60616263646566676869"
"70717273747576777879"
"80818283848586878889"
"90919293949596979899"
};
inline std::string& fast_itostr(int n, std::string& s, int padding)
{
if (n == 0)
{
s = std::string(padding, '0');
return s;
}
int sign = -(n < 0);
unsigned int val = (n^sign) - sign;
int size;
if (val >= 10000)
{
if (val >= 10000000)
{
if (val >= 1000000000)
size = 10;
else if (val >= 100000000)
size = 9;
else
size = 8;
}
else
{
if (val >= 1000000)
size = 7;
else if (val >= 100000)
size = 6;
else
size = 5;
}
}
else
{
if (val >= 100)
{
if (val >= 1000)
size = 4;
else
size = 3;
}
else
{
if (val >= 10)
size = 2;
else
size = 1;
}
}
size -= sign;
if (size < padding)
size = padding;
s.resize(size);
char* c = &s[0];
if (sign)
*c = '-';
c += size - 1;
while (val >= 100)
{
int pos = val % 100;
val /= 100;
*(short*)(c - 1) = *(short*)(digit_pairs + 2 * pos);
c -= 2;
}
while (val > 0)
{
*c-- = '0' + (val % 10);
val /= 10;
}
while (c >= s.data())
*c-- = '0';
return s;
}
}
}
|
