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#include <u.h>
#include <libc.h>
void
swap(char *a, char *b)
{
char tmp;
tmp = *a;
*a = *b;
*b = tmp;
}
void
srev(char *s, char *e)
{
while(s < e)
swap(s++, e--);
}
void
printdec(int n)
{
char buf[16];
char *p, *e;
int r;
p = buf;
e = buf+sizeof(buf)-1;
while(n > 0 && p < e){
r = n%10;
*p++ = '0'+r;
n /= 10;
}
*p = 0;
print("%s\n", buf);
}
void
usage(void)
{
fprint(2, "usage: %s number\n", argv0);
exits("usage");
}
void
main(int argc, char *argv[])
{
int n;
ARGBEGIN{
default: usage();
}ARGEND
if(argc != 1)
usage();
srev(argv[0], argv[0]+strlen(argv[0])-1);
n = strtol(argv[0], nil, 10);
printdec(n);
exits(0);
}
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