Решение задачи For 26

#include <bits/stdc++.h>
using namespace std;

int main() {
	srand((int)time(0));
	int N;
	N = rand() % 30 + 1;
	//N = 20;
	double X = (rand() % 20 - 10) / 10.0;
	//X = 0.1;
	
	double p = X, s = X;
	int k = 1;
	for(int i = 1; i <= N; i++) {
		p *= -1*X*X;
		k += 2;
		s += p/k;
		cout << i << " : "<< p << " : "<< s << endl;
	}
	cout << "Number N: " << N << endl;
	cout << "Number X: " << X << endl;
	cout << "Result: " << s << endl;
	cout << "atan(" << X <<") = " << atan(X) << endl;
	
	return 0;
}

import math
X = 0.8
N = 20
print('X = ', X)
print('N = ', N)

p = X
S = X
k = 1
for i in range(1,N+1):
    p *= -1*X*X
    k += 2
    S += p/k
    print(i," : ",k," : ",p," : ",S)

print("Result:")
print(S)
print("atan(x):")
print(math.atan(X))
									

program For26;
var
  X,Rez,pow:Real;
  N, i :Integer;
begin
  Write('Введите X: ');
  Readln(X);
  Write('Введите N: ');
  Readln(N);
  Rez:=0;
  pow:=1;
  For i:=1  to 2*N+1 do
   begin
   pow:=pow*X;
    if (i mod 2) <> 0 then
     begin
      Rez:=Rez+pow/i;
      pow:=pow*(-1);
     end;
   end;
  Writeln(Rez);
end.