UVa 637 - Booklet Printing

#include <cstdlib>
#include <cstring>
#include <cstdio>

int book[30][4];

int main()
{
int n;
while (~scanf("%d",&n) && n) {
int page = (n+3)/4;
memset(book ,0 ,sizeof(book));
int count = 1;
for (int i = 1 ; i <= page ; ++ i) {
book[i][1] = count ++;
if (count > n) break;
book[i][2] = count ++;
if (count > n) break;
}
if (count <= n)
for (int i = page ; i >= 1 ; -- i) {
book[i][3] = count ++;
if (count > n) break;
book[i][0] = count ++;
if (count > n) break;
}

printf("Printing order for %d pages:\n",n);
for (int i = 1 ; i <= page ; ++ i) {
if (book[i][0] || book[i][1]) {
printf("Sheet %d, front: ",i);
if (book[i][0]) printf("%d, ",book[i][0]);
else printf("Blank, ");
if (book[i][1]) printf("%d\n",book[i][1]);
else printf("Blank\n");
}
if (book[i][2] || book[i][3]) {
printf("Sheet %d, back : ",i);
if (book[i][2]) printf("%d, ",book[i][2]);
else printf("Blank, ");
if (book[i][3]) printf("%d\n",book[i][3]);
else printf("Blank\n");
}
}
}
return 0;
}