#define _CRT_SECURE_NO_WARNINGS #define _USE_MATH_DEFINES #include using namespace std; using i8 = int8_t; using u8 = uint8_t; using i16 = int16_t; using u16 = uint16_t; using i32 = int32_t; using u32 = uint32_t; using i64 = int64_t; using u64 = uint64_t; using f32 = float_t; using f64 = double_t; using usize = size_t;using str = string; template using vec = vector; #define times(n, i) for (i32 i = 0; i < (n); i++) #define range(n, m, i) for (u64 i = (n); i < (m); i++) #define upto(n, m, i) for (i32 i = (n); i <= (m); i++) #define downto(n, m, i) for (i32 i = (n); i >= (m); i--) #define foreach(xs, x) for (auto &x : (xs)) #define all(xs) (xs).begin(), (xs).end() #define sortall(xs) sort(all(xs)) #define reverseall(xs) reverse(all(xs)) #define uniqueall(xs) (xs).erase(unique(all(xs)), (xs).end()) #define maximum(xs) *max_element(all(xs)) #define minimum(xs) *min_element(all(xs)) const i64 MOD = 1000000007; i64 check(i32 n) { if (n == 3 || n == 5) return -1; if (n % 2 == 0) return 2; if (n % 3 == 0) return 3; if (n % 5 == 0) return 5; usize i = 7; i32 b = 0; while (i < n) { if (n % i == 0) return i; if (b == 0) i += 4; else i += 2; } return -1; } i32 main() { i32 L, H; cin >> L >> H; i64 p = 1; i64 ans = L; downto(H, L, x) { if (x <= p) break; i64 c = check(x); if (c < 0) continue; if (p < c) { p = c; ans = x; } } cout << ans << endl; return 0; }