The program is completely satisfied with the calculations, it multiplies 2 matrices of the specified size with random numbers, it starts and calculates correctly, but it shows that there are errors like: cin, cout, system are not unambiguous, only 17 errors, these operators underline in red how to remove it?

#include <iostream>
#include <ctime>
#include <iomanip>
using namespace std;
int main()
{
setlocale(LC_ALL, "Russian");
int** P1, ** P2, ** P3, n, m;
cout << "Enter count-in the rows of the matrix: ";
cin >> n;
cout << "Enter count-in the columns of the matrix: ";
cin >> m;
P1 = new int* [n];
for (int i = 0; i < n; i++)
    P1[i] = new int[m];
srand(time(0));
for (int i = 0; i < n; i++)
    for (int j = 0; j < m; j++)  //random1 matrices
        P1[i][j] = rand() % 10;
for (int i = 0; i < n; i++)
{
    cout << endl;                  //output1 matrices
    for (int j = 0; j < m; j++)
    {
        cout << setw(3) << P1[i][j] << "\t";
    }
}
cout << endl;
int k;
cout << "Enter count-in columns2 matrices: ";
cin >> k;
P2 = new int* [k];
for (int i = 0; i < m; i++)
    P2[i] = new int[k];
for (int i = 0; i < m; i++)
    for (int j = 0; j < k; j++)  //random2 matrices
        P2[i][j] = rand() % 10;
for (int i = 0; i < m; i++)
{
    cout << endl;                  //output2 matrices
    for (int j = 0; j < k; j++)
    {
        cout << setw(3) << P2[i][j] << "\t";
    }
}
cout << endl;
P3 = new int* [n];
for (int i = 0; i < n; i++)
    P3[i] = new int[k];
for (int i = 0; i < n; i++)
{
    for (int j = 0; j < k; j++)  //matrix multiplication
    {
        P3[i][j] = 0;
        for (int z = 0; z < m; z++)
            P3[i][j] = P3[i][j] + P1[i][z] * P2[z][j];
    }
}
cout << endl << "The result of the multiplication:" << endl;
for (int i = 0; i < n; i++)                     //output 
 multiplication
{
    cout << endl;
    for (int j = 0; j < k; j++)
        cout << setw(3) << P3[i][j] << "\t";
}
cout << endl;
for (int i = 0; i < n; i++)
    delete[] P1[i];
delete[] P1;
for (int i = 0; i < m; i++)
    delete[] P2[i];
delete[] P2;
for (int i = 0; i < n; i++)
    delete[] P3 [i];
delete[] P3;
system("pause");
return 0;
}

Answer 1, authority 100%

I myself constantly face this problem in VS. In practice it helps to erase and re-print the namespaced string (In your case: std). But I do not know the reasons for this problem. I assume this is an IntelliSense issue.

Answer 2

I don’t know why, but the errors disappeared by themselves, I just started the next day, fixed only deleting arrays, but here is a version of the program with correct deletion, everything went by itself, miracles

Answer 3

This is a project error, you just need to copy the code into a new project, but first you need to connect the libraries, and then paste the code