USACO section1.2 Dual Palindromes

/*
PROG: dualpal
LANG: C++
*/
# include <cstdio>
# include <cstring>

int n, s;

void strRev(char *s)
{
char ch;
int len = strlen(s), mid = len / 2;
for (int i = 0; i < mid; ++i)
ch = s[i], s[i] = s[len-1-i], s[len-1-i] = ch;
}

void to(int base, int x, char *s)
{
int i = 0;
while (x > 0)
{
s[i++]  = x % base + '0';
x /= base;
}
s[i] = '\0';
strRev(s);
}

char isPal(char *s)
{
int len = strlen(s), mid = len / 2;
for (int i = 0; i < mid; ++i)
if (s[i] != s[len-1-i]) return 0;
return 1;
}

int main()
{
freopen("dualpal.in", "r", stdin);
freopen("dualpal.out", "w", stdout);

scanf("%d%d", &n, &s);
int cnt = 0;
char buf[30];
for (int i = s+1; cnt < n; ++i)
{
char ok = 0;
int c = 0;
for (int j = 2; j <= 10; ++j)
{
to(j, i, buf);
if (isPal(buf)) ++c;
if (c >= 2) {ok = 1; break;}
}
if (ok) {printf("%d\n", i);++cnt;}
}

fclose(stdin);
fclose(stdout);

return 0;
}