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#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <errno.h>
#include <limits.h>
#include <math.h>
#include "EXTERN.h"
#include "perl.h"
#include "ppport.h"
static U32 len_table_u32[] = {
9, 99, 999, 9999,
99999, 999999, 9999999, 99999999,
999999999, UINT_MAX
};
U8
uint32_length(U32 num)
{
U8 i;
for (i = 0;; ++i) {
if (num < len_table_u32[i])
return i+1;
}
}
#ifndef U64_CONST
# define U64_CONST(x) ((uint64_t)x##UL)
#endif
static uint64_t len_table_u64[] = {
9, 99, 999, 9999,
99999, 999999, 9999999, 99999999,
U64_CONST(999999999),
U64_CONST(9999999999),
U64_CONST(99999999999),
U64_CONST(999999999999),
U64_CONST(9999999999999),
U64_CONST(99999999999999),
U64_CONST(999999999999999),
U64_CONST(9999999999999999),
U64_CONST(99999999999999999),
U64_CONST(999999999999999999),
U64_CONST(9999999999999999999),
U64_CONST(18446744073709551615)
};
U8
uint64_length(uint64_t num)
{
U8 i;
for (i = 0;; ++i) {
if (num < len_table_u64[i])
return i+1;
}
}
U8
uint64_length_2(uint64_t num)
{
U8 len = 0;
unsigned int tmp = 1UL;
while(tmp < num)
{
++len;
tmp = (tmp << 3) + (tmp << 1);
}
return len;
}
U8
uint64_length_3(uint64_t num)
{
return (U8)floor( log10( num ) ) + 1;
}
#define CASE(n,i) if (num < (uint64_t)(n##UL)) return i
U8
uint64_length_4(uint64_t num)
{
CASE(9, 1);
CASE(99, 2);
CASE(999, 3);
CASE(9999, 4);
CASE(99999, 5);
CASE(999999, 6);
CASE(9999999, 7);
CASE(99999999, 8);
CASE(999999999, 9);
CASE(9999999999, 10);
CASE(99999999999, 11);
CASE(999999999999, 12);
CASE(9999999999999, 13);
CASE(99999999999999, 14);
CASE(999999999999999, 15);
CASE(9999999999999999, 16);
CASE(99999999999999999, 17);
CASE(999999999999999999, 18);
CASE(9999999999999999999, 19);
return 20;
}
#undef CASE
int
main(int argc, char** argv) {
unsigned int i = 0;
for (i = 0; i < 300000000; ++i) {
uint64_length_4(i);
}
return 1;
}
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