A number is called almost prime if it has exactly two distinct prime divisors. For example, numbers 6, 18, 24 are almost prime, while 4, 8, 9, 42 are not. Find the amount of almost prime numbers which are between 1 and n, inclusive.

Input

Input contains one integer number n (1 ≤ n ≤ 3000).

Output

Output the amount of almost prime numbers between 1 and n, inclusive.

Examples

Input

10


Output

2


Input

21


Output

8
hat = int(input())
primes = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41,
          43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97,
          101, 103, 107, 109, 113, 127, 131, 137, 139, 149,
          151, 157, 163, 167, 173, 179, 181, 191, 193, 197,
          199, 211, 223, 227, 229, 233, 239, 241, 251, 257,
          263, 269, 271, 277, 281, 283, 293, 307, 311, 313,
          317, 331, 337, 347, 349, 353, 359, 367, 373, 379,
          383, 389, 397, 401, 409, 419, 421, 431, 433, 439,
          443, 449, 457, 461, 463, 467, 479, 487, 491, 499,
          503, 509, 521, 523, 541, 547, 557, 563, 569, 571,
          577, 587, 593, 599, 601, 607, 613, 617, 619, 631,
          641, 643, 647, 653, 659, 661, 673, 677, 683, 691,
          701, 709, 719, 727, 733, 739, 743, 751, 757, 761,
          769, 773, 787, 797, 809, 811, 821, 823, 827, 829,
          839, 853, 857, 859, 863, 877, 881, 883, 887, 907,
          911, 919, 929, 937, 941, 947, 953, 967, 971, 977,
          983, 991, 997, 1009, 1013, 1019, 1021, 1031, 1033,
          1039, 1049, 1051, 1061, 1063, 1069, 1087, 1091, 1093,
          1097, 1103, 1109, 1117, 1123, 1129, 1151, 1153, 1163,
          1171, 1181, 1187, 1193, 1201, 1213, 1217, 1223, 1229,
          1231, 1237, 1249, 1259, 1277, 1279, 1283, 1289, 1291,
          1297, 1301, 1303, 1307, 1319, 1321, 1327, 1361, 1367,
          1373, 1381, 1399, 1409, 1423, 1427, 1429, 1433, 1439,
          1447, 1451, 1453, 1459, 1471, 1481, 1483, 1487, 1489,
          1493, 1499, 1511, 1523, 1531, 1543, 1549, 1553, 1559,
          1567, 1571, 1579, 1583, 1597, 1601, 1607, 1609, 1613,
          1619, 1621, 1627, 1637, 1657, 1663, 1667, 1669, 1693,
          1697, 1699, 1709, 1721, 1723, 1733, 1741, 1747, 1753,
          1759, 1777, 1783, 1787, 1789, 1801, 1811, 1823, 1831,
          1847, 1861, 1867, 1871, 1873, 1877, 1879, 1889, 1901,
          1907, 1913, 1931, 1933, 1949, 1951, 1973, 1979, 1987, 1993,
          1997, 1999, 2003, 2011, 2017, 2027, 2029, 2039, 2053, 2063,
          2069, 2081, 2083, 2087, 2089, 2099, 2111, 2113, 2129, 2131,
          2137, 2141, 2143, 2153, 2161, 2179, 2203, 2207, 2213, 2221,
          2237, 2239, 2243, 2251, 2267, 2269, 2273, 2281, 2287, 2293,
          2297, 2309, 2311, 2333, 2339, 2341, 2347, 2351, 2357, 2371,
          2377, 2381, 2383, 2389, 2393, 2399, 2411, 2417, 2423, 2437,
          2441, 2447, 2459, 2467, 2473, 2477, 2503, 2521, 2531, 2539,
          2543, 2549, 2551, 2557, 2579, 2591, 2593, 2609, 2617, 2621,
          2633, 2647, 2657, 2659, 2663, 2671, 2677, 2683, 2687, 2689,
          2693, 2699, 2707, 2711, 2713, 2719, 2729, 2731, 2741, 2749,
          2753, 2767, 2777, 2789, 2791, 2797, 2801, 2803, 2819, 2833,
          2837, 2843, 2851, 2857, 2861, 2879, 2887, 2897, 2903, 2909,
          2917, 2927, 2939, 2953, 2957, 2963, 2969, 2971, 2999]


good = 0
for i in range(1, hat+1):
    can = 0
    for j in primes:
        if j > i:
            break
        elif i % j == 0:
            can += 1
    if can == 2:
        good += 1
print(good)
