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#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/mman.h>
#include "types.h"
int length;
static u8 *map_file(const char *name)
{
int fd = open(name, O_RDONLY);
length = lseek(fd, 0, SEEK_END);
void *map = mmap(0, length, PROT_READ, MAP_SHARED, fd, 0);
close(fd);
return map;
}
int main(int argc, const char **argv)
{
int n = argc - 1;
u8 *data[n];
int i, j;
for (i = 0; i < n; i++)
data[i] = map_file(argv[i + 1]);
for (j = 0; j < length; j++) {
int a[256];
memset(a, 0, sizeof a);
for (i = 0; i < n; i++)
a[data[i][j]]++;
int max = 0;
u8 imax = 0;
for (i = 0; i < 256; i++)
if (a[i] > max) {
max = a[i];
imax = i;
}
write(1, &imax, 1);
if (max < n-1) {
fprintf(stderr, "warning: at least two outliers @ %06x:", j);
for (i = 0; i < n; i++)
fprintf(stderr, " %02x", data[i][j]);
fprintf(stderr, " (picked %02x)\n", imax);
}
}
return 0;
}
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