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#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <utility>
#include <math.h>

using namespace std;

typedef pair<double, double> pdd;
const double dx = 0.0001;

double f(double x) {
    return log(cos(x)) + cos(x);
}


void print(pdd p) {
    cout << p.first << " " << p.second << endl;
}


pdd SvenMax(double x0, double h) {
    double f1 = f(x0);
    double f2 = f(x0 + h);
    double f0 = f(x0 - h);
    int k = 1;
    double x1, x2;

    if (f0 >= f1 && f1 >= f2) {
        x1 = x0 - h;
        h = -h;
    }
    else if (f0 <= f1 && f1 <= f2) {
        x1 = x0 + h;
    }
    else {
        return pdd(x0 - h, x0 + h);
    }

    x2 = x1;
    x1 = x0;
    do {
        x0 = x1;
        x1 = x2;
        x2 = x1 + pow(2, 1.0 * k) * h;
        k++;
    } while (f(x2) >= f(x1));

    if (h > 0) {
        return pdd(x0, x2);
    }
    else {
        return pdd(x2, x0);
    }

}

double PD(pdd t, double e) {
    double a = t.first;
    double b = t.second;
    double x1, x2;
    double xc = (a + b) / 2;
    double l = b - a;
    while (l > e) {
        x1 = a + l / 4;
        x2 = b - l / 4;
        if (f(x1) > f(xc)) {
            b = xc;
            xc = x1;
        }
        else if (f(x2) > f(xc)) {
            a = xc;
            xc = x2;
        }
        else {
            a = x1;
            b = x2;
        }
        l = b - a;
    }
    return xc;
}

int main(void) {

    pdd a = SvenMax(-1, 1);
    cout << "cut: ";
    print(a);

    double b = PD(a, 0.00001);
    cout << "max: ";

    cout << "(" << b << ";" << f(b) << ")" << endl;
    return 0;
}