Объяснение:
1
#include <iostream>
using namespace std;
int main()
{
int a, b;
cin>>a>>b;
int p = (a + b) * 2;
int pl = a * b;
cout<<"Perimetr: "<<p;
cout<<"Ploshad: "<<pl;
}
2
#include <iostream>
using namespace std;
int main()
{
int l;
float r, d;
cin>>l;
r = l / 2 / 3.14;
d = r * 2;
cout<<"Radius: "<<r;
cout<<"Diametr: "<<d;
}
3
#include <iostream>
using namespace std;
void Reverse(char *numb)
{
char help;
int N = 3;
for (int i = 0; i < N / 2; i++)
{
help = numb[i];
numb[i] = numb[N - 1 - i];
numb[N - 1 - i] = help;
}
for (int i = 0; i < N; i++)
cout << numb[i];
}
int main(int argc, char const *argv[])
{
const int N = 3;
char numb[N];
cin >> numb;
Reverse(numb);
}
random_device rd;
mt19937 eng(rd());
uniform_int_distribution<int> dist(1, 10);
int n;
int x;
cin >> n >> x;
vector<int> a(n);
for (auto& i : a)
i = dist(eng);
copy(a.cbegin(), a.cend(), ostream_iterator<int>(cout, " "));
cout << '\n';
sort(a.begin(), a.end());
copy(a.cbegin(), a.cend(), ostream_iterator<int>(cout, " "));
cout << '\n';
if (binary_search(a.cbegin(), a.cend(), x)) {
cout << x << " found";
} else {
set<int> temp(a.cbegin(), a.cend());
if (x < *temp.cbegin()) {
cout << *temp.cbegin();
} else if (x > *prev(temp.cend())) {
cout << *prev(temp.cend());
} else {
auto f = lower_bound(a.cbegin(), a.cend(), x);
auto s = upper_bound(a.cbegin(), a.cend(), x);
if (f != a.cend() && s != a.cend()) {
if (abs(*f - x) < abs(*s - x)) {
cout << *f;
} else {
cout << *s;
}
} else if (f == a.cend() && s != a.cend()) {
cout << *s;
} else if (f != a.cend() && s == a.cend()) {
cout << *f;
}
}
}