#ifndef KK2_TEMPLATE_PROCON_HPP
#define KK2_TEMPLATE_PROCON_HPP 1

#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <deque>
#include <fstream>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <map>
#include <numeric>
#include <optional>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

#ifndef KK2_TEMPLATE_CONSTANT_HPP
#define KK2_TEMPLATE_CONSTANT_HPP 1

#ifndef KK2_TEMPLATE_TYPE_ALIAS_HPP
#define KK2_TEMPLATE_TYPE_ALIAS_HPP 1

#include <functional>
#include <queue>
#include <utility>
#include <vector>

using u32 = unsigned int;
using i64 = long long;
using u64 = unsigned long long;
using i128 = __int128_t;
using u128 = __uint128_t;

using pi = std::pair<int, int>;
using pl = std::pair<i64, i64>;
using pil = std::pair<int, i64>;
using pli = std::pair<i64, int>;

template <class T> using vc = std::vector<T>;
template <class T> using vvc = std::vector<vc<T>>;
template <class T> using vvvc = std::vector<vvc<T>>;
template <class T> using vvvvc = std::vector<vvvc<T>>;

template <class T> using pq = std::priority_queue<T>;
template <class T> using pqi = std::priority_queue<T, std::vector<T>, std::greater<T>>;

#endif // KK2_TEMPLATE_TYPE_ALIAS_HPP

// #include "type_alias.hpp"

template <class T> constexpr T infty = 0;
template <> constexpr int infty<int> = (1 << 30) - 123;
template <> constexpr i64 infty<i64> = (1ll << 62) - (1ll << 31);
template <> constexpr i128 infty<i128> = (i128(1) << 126) - (i128(1) << 63);
template <> constexpr u32 infty<u32> = infty<int>;
template <> constexpr u64 infty<u64> = infty<i64>;
template <> constexpr u128 infty<u128> = infty<i128>;
template <> constexpr double infty<double> = infty<i64>;
template <> constexpr long double infty<long double> = infty<i64>;

constexpr int mod = 998244353;
constexpr int modu = 1e9 + 7;
constexpr long double PI = 3.14159265358979323846;

#endif // KK2_TEMPLATE_CONSTANT_HPP

// #include "constant.hpp"
#ifndef KK2_TEMPLATE_FUNCTION_UTIL_HPP
#define KK2_TEMPLATE_FUNCTION_UTIL_HPP 1

#include <algorithm>
#include <vector>

namespace kk2 {

template <class T, class... Sizes> auto make_vector(int first, Sizes... sizes) {
    if constexpr (sizeof...(sizes) == 0) {
        return std::vector<T>(first);
    } else {
        return std::vector<decltype(make_vector<T>(sizes...))>(first, make_vector<T>(sizes...));
    }
}

template <class T, class U> void fill_all(std::vector<T> &v, const U &x) {
    std::fill(std::begin(v), std::end(v), T(x));
}

template <class T, class U> void fill_all(std::vector<std::vector<T>> &v, const U &x) {
    for (auto &u : v) fill_all(u, x);
}

template <class C> int mysize(const C &c) {
    return c.size();
}

// T: comutative monoid
template <class T, class U> U all_sum(const std::vector<T> &v, U init, U = U()) {
    U res = init;
    for (const auto &x : v) res += x;
    return res;
}

template <class T, class U> U all_sum(const std::vector<std::vector<T>> &v, U init, U unit = U()) {
    U res = init;
    for (const auto &u : v) res += all_sum(u, unit, unit);
    return res;
}

// T: commutative monoid, F: (U, T) -> U
template <class T, class U, class F> U all_prod(const std::vector<T> &v, U init, const F &f, U = U()) {
    U res = init;
    for (const auto &x : v) res = f(res, x);
    return res;
}

template <class T, class U, class F>
U all_prod(const std::vector<std::vector<T>> &v, U init, const F &f, U unit) {
    U res = init;
    for (const auto &u : v) res = f(res, all_prod(u, unit, f, unit));
    return res;
}

template <class T> T all_min(const std::vector<T> &v) {
    if (v.empty()) return T();
    T res = v[0];
    for (const auto &x : v) res = res > x ? x : res;
    return res;
}

template <class T>
T all_min(const std::vector<std::vector<T>> &v) {
    T res{};
    bool first = true;
    for (const auto &u : v) {
        if (u.empty()) continue;
        if (first) {
            res = all_min(u);
            first = false;
        } else {
            T tmp = all_min(u);
            res = res > tmp ? tmp : res;
        }
    }
    return res;
}

template <class T> T all_max(const std::vector<T> &v) {
    if (v.empty()) return T();
    T res = v[0];
    for (const auto &x : v) res = res < x ? x : res;
    return res;
}

template <class T>
T all_max(const std::vector<std::vector<T>> &v) {
    T res{};
    bool first = true;
    for (const auto &u : v) {
        if (u.empty()) continue;
        if (first) {
            res = all_max(u);
            first = false;
        } else {
            T tmp = all_max(u);
            res = res < tmp ? tmp : res;
        }
    }
    return res;
}

} // namespace kk2

#endif // KK2_TEMPLATE_FUNCTION_UTIL_HPP

// #include "function_util.hpp"
#ifndef KK2_TEMPLATE_IO_UTIL_HPP
#define KK2_TEMPLATE_IO_UTIL_HPP 1

#include <array>
#include <utility>
#include <vector>

#ifndef KK2_TYPE_TRAITS_TYPE_TRAITS_HPP
#define KK2_TYPE_TRAITS_TYPE_TRAITS_HPP 1


#include <istream>
#include <ostream>
#include <type_traits>

namespace kk2 {

#ifndef _MSC_VER

template <typename T>
using is_signed_int128 = typename std::conditional<std::is_same<T, __int128_t>::value
                                                       or std::is_same<T, __int128>::value,
                                                   std::true_type,
                                                   std::false_type>::type;

template <typename T>
using is_unsigned_int128 =
    typename std::conditional<std::is_same<T, __uint128_t>::value
                                  or std::is_same<T, unsigned __int128>::value,
                              std::true_type,
                              std::false_type>::type;

template <typename T>
using is_integral =
    typename std::conditional<std::is_integral<T>::value or is_signed_int128<T>::value
                                  or is_unsigned_int128<T>::value,
                              std::true_type,
                              std::false_type>::type;

template <typename T>
using is_signed = typename std::conditional<std::is_signed<T>::value or is_signed_int128<T>::value,
                                            std::true_type,
                                            std::false_type>::type;

template <typename T>
using is_unsigned =
    typename std::conditional<std::is_unsigned<T>::value or is_unsigned_int128<T>::value,
                              std::true_type,
                              std::false_type>::type;

template <typename T>
using make_unsigned_int128 =
    typename std::conditional<std::is_same<T, __int128_t>::value, __uint128_t, unsigned __int128>;

template <typename T>
using to_unsigned =
    typename std::conditional<is_signed_int128<T>::value,
                              make_unsigned_int128<T>,
                              typename std::conditional<std::is_signed<T>::value,
                                                        std::make_unsigned<T>,
                                                        std::common_type<T>>::type>::type;

#else

template <typename T> using is_integral = std::enable_if_t<std::is_integral<T>::value>;
template <typename T> using is_signed = std::enable_if_t<std::is_signed<T>::value>;
template <typename T> using is_unsigned = std::enable_if_t<std::is_unsigned<T>::value>;
template <typename T> using to_unsigned = std::make_unsigned<T>;

#endif // _MSC_VER

template <typename T> using is_integral_t = std::enable_if_t<is_integral<T>::value>;
template <typename T> using is_signed_t = std::enable_if_t<is_signed<T>::value>;
template <typename T> using is_unsigned_t = std::enable_if_t<is_unsigned<T>::value>;


template <typename T>
using is_function_pointer =
    typename std::conditional<std::is_pointer_v<T> && std::is_function_v<std::remove_pointer_t<T>>,
                              std::true_type,
                              std::false_type>::type;

template <typename T, std::enable_if_t<is_function_pointer<T>::value> * = nullptr>
struct is_two_args_function_pointer : std::false_type {};

template <typename R, typename T1, typename T2>
struct is_two_args_function_pointer<R (*)(T1, T2)> : std::true_type {};

template <typename T>
using is_two_args_function_pointer_t = std::enable_if_t<is_two_args_function_pointer<T>::value>;

namespace type_traits {

struct istream_tag {};

struct ostream_tag {};

} // namespace type_traits

template <typename T>
using is_standard_istream = typename std::conditional<std::is_same<T, std::istream>::value
                                                          || std::is_same<T, std::ifstream>::value,
                                                      std::true_type,
                                                      std::false_type>::type;
template <typename T>
using is_standard_ostream = typename std::conditional<std::is_same<T, std::ostream>::value
                                                          || std::is_same<T, std::ofstream>::value,
                                                      std::true_type,
                                                      std::false_type>::type;
template <typename T> using is_user_defined_istream = std::is_base_of<type_traits::istream_tag, T>;
template <typename T> using is_user_defined_ostream = std::is_base_of<type_traits::ostream_tag, T>;

template <typename T>
using is_istream =
    typename std::conditional<is_standard_istream<T>::value || is_user_defined_istream<T>::value,
                              std::true_type,
                              std::false_type>::type;

template <typename T>
using is_ostream =
    typename std::conditional<is_standard_ostream<T>::value || is_user_defined_ostream<T>::value,
                              std::true_type,
                              std::false_type>::type;

template <typename T> using is_istream_t = std::enable_if_t<is_istream<T>::value>;
template <typename T> using is_ostream_t = std::enable_if_t<is_ostream<T>::value>;


} // namespace kk2

#endif // KK2_TYPE_TRAITS_TYPE_TRAITS_HPP

// #include "../type_traits/type_traits.hpp"

// なんかoj verifyはプロトタイプ宣言が落ちる

namespace impl {

struct read {
    template <class IStream, class T> static void all_read(IStream &is, T &x) { is >> x; }

    template <class IStream, class T, class U>
    static void all_read(IStream &is, std::pair<T, U> &p) {
        all_read(is, p.first);
        all_read(is, p.second);
    }

    template <class IStream, class T> static void all_read(IStream &is, std::vector<T> &v) {
        for (T &x : v) all_read(is, x);
    }

    template <class IStream, class T, size_t F>
    static void all_read(IStream &is, std::array<T, F> &a) {
        for (T &x : a) all_read(is, x);
    }
};

struct write {
    template <class OStream, class T> static void all_write(OStream &os, const T &x) { os << x; }

    template <class OStream, class T, class U>
    static void all_write(OStream &os, const std::pair<T, U> &p) {
        all_write(os, p.first);
        all_write(os, ' ');
        all_write(os, p.second);
    }

    template <class OStream, class T> static void all_write(OStream &os, const std::vector<T> &v) {
        for (int i = 0; i < (int)v.size(); ++i) {
            if (i) all_write(os, ' ');
            all_write(os, v[i]);
        }
    }

    template <class OStream, class T, size_t F>
    static void all_write(OStream &os, const std::array<T, F> &a) {
        for (int i = 0; i < (int)F; ++i) {
            if (i) all_write(os, ' ');
            all_write(os, a[i]);
        }
    }
};

} // namespace impl

template <class IStream, class T, class U, kk2::is_istream_t<IStream> * = nullptr>
IStream &operator>>(IStream &is, std::pair<T, U> &p) {
    impl::read::all_read(is, p);
    return is;
}

template <class IStream, class T, kk2::is_istream_t<IStream> * = nullptr>
IStream &operator>>(IStream &is, std::vector<T> &v) {
    impl::read::all_read(is, v);
    return is;
}

template <class IStream, class T, size_t F, kk2::is_istream_t<IStream> * = nullptr>
IStream &operator>>(IStream &is, std::array<T, F> &a) {
    impl::read::all_read(is, a);
    return is;
}

template <class OStream, class T, class U, kk2::is_ostream_t<OStream> * = nullptr>
OStream &operator<<(OStream &os, const std::pair<T, U> &p) {
    impl::write::all_write(os, p);
    return os;
}

template <class OStream, class T, kk2::is_ostream_t<OStream> * = nullptr>
OStream &operator<<(OStream &os, const std::vector<T> &v) {
    impl::write::all_write(os, v);
    return os;
}

template <class OStream, class T, size_t F, kk2::is_ostream_t<OStream> * = nullptr>
OStream &operator<<(OStream &os, const std::array<T, F> &a) {
    impl::write::all_write(os, a);
    return os;
}

#endif // KK2_TEMPLATE_IO_UTIL_HPP

// #include "io_util.hpp"
#ifndef KK2_TEMPLATE_MACROS_HPP
#define KK2_TEMPLATE_MACROS_HPP 1

#define rep1(a) for (long long _ = 0; _ < (long long)(a); ++_)
#define rep2(i, a) for (long long i = 0; i < (long long)(a); ++i)
#define rep3(i, a, b) for (long long i = (a); i < (long long)(b); ++i)
#define repi2(i, a) for (long long i = (a) - 1; i >= 0; --i)
#define repi3(i, a, b) for (long long i = (a) - 1; i >= (long long)(b); --i)
#define overload3(a, b, c, d, ...) d
#define rep(...) overload3(__VA_ARGS__, rep3, rep2, rep1)(__VA_ARGS__)
#define repi(...) overload3(__VA_ARGS__, repi3, repi2, rep1)(__VA_ARGS__)

#define fi first
#define se second
#define all(p) p.begin(), p.end()

#endif // KK2_TEMPLATE_MACROS_HPP

// #include "macros.hpp"
// #include "type_alias.hpp"

struct FastIOSetUp {
    FastIOSetUp() {
        std::ios::sync_with_stdio(false);
        std::cin.tie(nullptr);
    }
} fast_io_set_up;

auto &kin = std::cin;
auto &kout = std::cout;
auto (*kendl)(std::ostream &) = std::endl<char, std::char_traits<char>>;

void Yes(bool b = 1) {
    kout << (b ? "Yes\n" : "No\n");
}

void No(bool b = 1) {
    kout << (b ? "No\n" : "Yes\n");
}

void YES(bool b = 1) {
    kout << (b ? "YES\n" : "NO\n");
}

void NO(bool b = 1) {
    kout << (b ? "NO\n" : "YES\n");
}

void yes(bool b = 1) {
    kout << (b ? "yes\n" : "no\n");
}

void no(bool b = 1) {
    kout << (b ? "no\n" : "yes\n");
}

template <class T, class S> inline bool chmax(T &a, const S &b) {
    return (a < b ? a = b, 1 : 0);
}

template <class T, class S> inline bool chmin(T &a, const S &b) {
    return (a > b ? a = b, 1 : 0);
}

std::istream &operator>>(std::istream &is, u128 &x) {
    std::string s;
    is >> s;
    x = 0;
    for (char c : s) {
        assert('0' <= c && c <= '9');
        x = x * 10 + c - '0';
    }
    return is;
}

std::istream &operator>>(std::istream &is, i128 &x) {
    std::string s;
    is >> s;
    bool neg = s[0] == '-';
    x = 0;
    for (int i = neg; i < (int)s.size(); i++) {
        assert('0' <= s[i] && s[i] <= '9');
        x = x * 10 + s[i] - '0';
    }
    if (neg) x = -x;
    return is;
}

std::ostream &operator<<(std::ostream &os, u128 x) {
    if (x == 0) return os << '0';
    std::string s;
    while (x) {
        s.push_back('0' + x % 10);
        x /= 10;
    }
    std::reverse(s.begin(), s.end());
    return os << s;
}

std::ostream &operator<<(std::ostream &os, i128 x) {
    if (x == 0) return os << '0';
    if (x < 0) {
        os << '-';
        x = -x;
    }
    std::string s;
    while (x) {
        s.push_back('0' + x % 10);
        x /= 10;
    }
    std::reverse(s.begin(), s.end());
    return os << s;
}

#endif // KK2_TEMPLATE_PROCON_HPP

// #include <kk2/template/procon.hpp>
// #include <kk2/template/debug.hpp>
#ifndef KK2_MATH_SQRT_FLOOR_HPP
#define KK2_MATH_SQRT_FLOOR_HPP 1

#include <cmath>

#ifndef KK2_MATH_FRAC_FLOOR_HPP
#define KK2_MATH_FRAC_FLOOR_HPP 1

#include <cassert>

namespace kk2 {

// floor(x) = ceil(x) - 1 (for all x not in Z) ...(1)
// floor(x) = -ceil(-x)   (for all x)          ...(2)

// return floor(a / b)
template <typename T, typename U> constexpr T fracfloor(T a, U b) {
    assert(b != 0);
    if (a % b == 0) return a / b;
    if (a >= 0) return a / b;

    // floor(x) = -ceil(-x)      by (2)
    //          = -floor(-x) - 1 by (1)
    return -((-a) / b) - 1;
}

// return ceil(a / b)
template <typename T, typename U> constexpr T fracceil(T a, U b) {
    assert(b != 0);
    if (a % b == 0) return a / b;
    if (a >= 0) return a / b + 1;

    // ceil(x) = -floor(-x)      by (2)
    return -((-a) / b);
}

} // namespace kk2

#endif // KK2_MATH_FRAC_FLOOR_HPP

// #include "frac_floor.hpp"

namespace kk2 {

template <typename T> T sqrt_floor(T n) {
    assert(n >= 0);
    if (n == T(0)) return 0;
    T x = std::sqrt(n);
    if (x == T(0)) ++x;
    while (x > kk2::fracfloor(n, x)) --x;
    while (x + 1 <= kk2::fracfloor(n, x + 1)) ++x;
    return x;
}

template <typename T> T sqrt_ceil(T n) {
    assert(n >= 0);
    if (n <= T(1)) return n;
    T x = std::sqrt(n);
    if (x == T(0)) ++x;
    while (x < kk2::fracceil(n, x)) ++x;
    while (x - 1 >= kk2::fracceil(n, x - 1)) --x;
    return x;
}

} // namespace kk2

#endif // KK2_MATH_SQRT_FLOOR_HPP

// #include <kk2/math/sqrt_floor.hpp>
using namespace std;

void solve() {
    i64 n;
    kin >> n;
    int sqrt_n = kk2::sqrt_floor(n);
    kout << sqrt_n + n / (sqrt_n + 1) << endl;
}

int main() {
    int t = 1;
    // kin >> t;
    rep (t) solve();

    return 0;
}

// converted!!
// Author: kk2
// 2025-01-31 14:25:24