#include #include #define incID(i, l, r) for(int i = (l) ; i < (r); i++) #define incII(i, l, r) for(int i = (l) ; i <= (r); i++) #define decID(i, l, r) for(int i = (r) - 1; i >= (l); i--) #define decII(i, l, r) for(int i = (r) ; i >= (l); i--) #define inc( i, n) incID(i, 0, n) #define inc1(i, n) incII(i, 1, n) #define dec( i, n) decID(i, 0, n) #define dec1(i, n) decII(i, 1, n) typedef long long signed int LL; typedef long long unsigned int LU; template void swap(T &x, T &y) { T t = x; x = y; y = t; return; } template T abs(T x) { return (0 <= x ? x : -x); } template T max(T a, T b) { return (b <= a ? a : b); } template T min(T a, T b) { return (a <= b ? a : b); } template bool setmin(T &a, T b) { if(a <= b) { return false; } else { a = b; return true; } } template bool setmax(T &a, T b) { if(b <= a) { return false; } else { a = b; return true; } } template T gcd(T a, T b) { return (b == 0 ? a : gcd(b, a % b)); } template T lcm(T a, T b) { return a / gcd(a, b) * b; } // ---- ---- char n[10002]; int b[10]; int main() { /* printf("> "); int x, y, z; scanf("%d%d", &x, &y); printf("gcd(%d, %d) = %d\n", x, y, gcd(x,y) ); return 0; */ scanf("%s", n); int l = 0; while(n[l] != '\0') { b[ n[l] - '0' ]++; l++; } int m = 0; inc(i, 10) { if(b[i]) { m++; } } if(m == 1) { printf("%s\n", n); return 0; } if(m == 2 && b[0]) { inc(i, l - b[0]) { printf("%c", n[0]); } printf("\n"); return 0; } return 1; int ans = 0; incII(i, 0, 9) { incID(j, 0, i) { if(b[i] && b[j]) { ans = gcd(ans, gcd(i, j)); } } } if(ans != 1) { ans *= 9; } printf("%d\n", ans); return 0; }