ZOJ 3490 String Successor

#include<stdio.h>
#include<string.h>
#include<math.h>
#include<algorithm>
using namespace std;
const int maxn = 111;
char s[maxn];
char ji[maxn];
int gg[maxn];
void RevStr(char *str)
{
int len;
char *ptr;
len = strlen(str);
ptr = str + len - 1;
while (str != ptr)
{
char ch; ch = *str; *str = *ptr; *ptr = ch; str++;
if (str == ptr)break;
else ptr--;
}
}
int main()
{
int n, i, y, m;
int sb;
scanf("%d", &n);
for (sb = 0; sb < n; sb++)
{
memset(s, 0, sizeof(s));
memset(ji, 0, sizeof(ji));
scanf("%s", s);
scanf("%d", &m);
y = strlen(s);
int q = 0;
for (i = 0; i < y; i++)
{
if ((s[i] >= '0'&&s[i] <= '9') || (s[i] >= 'a'&&s[i] <= 'z') || (s[i] >= 'A'&&s[i] <= 'Z'))
{
ji[q] = s[i];
gg[q] = i;
q++;
}
}
int bu = 0;
while (q == 0)
{
s[y - 1]++;
printf("%s\n", s);
if ((s[y - 1] >= '0'&&s[y - 1] <= '9') || (s[y - 1] >= 'a'&&s[y - 1] <= 'z') || (s[y - 1] >= 'A'&&s[y - 1] <= 'Z'))
{
ji[q] = s[y - 1];
gg[q] = y - 1;
q++;
}
bu++;
if (bu >= m) break;
}
if (bu < m)
{
for (i = 0; i < q / 2; i++)
{
int t = gg[i];
gg[i] = gg[q - i - 1];
gg[q - i - 1] = t;
}
RevStr(ji);
while (1)
{
int zhi = 0;
while (1)
{
if (zhi == q)
{
if (ji[zhi - 1] >= '0'&&ji[zhi - 1] <= '9'){ ji[zhi] = '1'; gg[zhi] = gg[zhi - 1]; }
else if (ji[zhi - 1] >= 'a'&&ji[zhi - 1] <= 'z'){ ji[zhi] = 'a'; gg[zhi] = gg[zhi - 1]; }
else if (ji[zhi - 1] >= 'A'&&ji[zhi - 1] <= 'Z'){ ji[zhi] = 'A'; gg[zhi] = gg[zhi - 1]; }
q++;
break;
}
if (ji[zhi] == '9'){ ji[zhi] = '0'; zhi++; }
else if (ji[zhi] == 'z'){ ji[zhi] = 'a'; zhi++; }
else if (ji[zhi] == 'Z'){ ji[zhi] = 'A'; zhi++; }
else { ji[zhi]++; break; }
}
zhi = q - 1;
for (i = 0; i < y; i++)
{
int flag = 0;
while (gg[zhi] == i&&zhi >= 0)
{
printf("%c", ji[zhi]);
zhi--;
flag = 1;
}
if (flag == 0) printf("%c", s[i]);
}
printf("\n");
bu++;
if (bu >= m) break;
}
}
printf("\n");
}
return 0;
}