Задача для Сёмы

#include <iostream>
#include "ctime"
using namespace std;
int main() {
    const int n = 5;
    int a[n][n];

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            a[i][j] = rand() % 100 - 50;
        }
    }
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            cout << a[i][j] << '\t';
        }
        cout << endl;
    }
    cout << endl;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (i < j) {
                a[i][j] = 0;
            }
            if (i > j) {
                a[i][j] = -1;
            }
        }
    }
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            cout << a[i][j] << '\t';
        }
        cout << endl;
    }
    cout << endl;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (i + j < n - 1) {
                a[i][j] = -2;
            }
            if (i + j > n - 1) {
                a[i][j] = -3;
            }
        }
    }
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            cout << a[i][j] << '\t';
        }
        cout << endl;
    }
}