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  1. #include <iostream>
  2. #include <cmath>
  3. #include <cstdlib>
  4. #include <ctime>
  5.  
  6. using namespace std;
  7.  
  8. int
  9. pos(int s, int row, int col)
  10. {
  11.     if (row > col) {
  12.         int tmp = row;
  13.         row = col;
  14.         col = tmp;
  15.     }
  16.     return (col - row + (s + s - row + 1) * row / 2);
  17. }
  18.  
  19. void
  20. print_matrix1(int a[], int n)
  21. {
  22.     for (int i = 0; i < n; ++i) {
  23.         for (int j = 0; j < n; ++j) {
  24.             cout << a[pos(n, i, j)] << " ";
  25.         }
  26.         cout << endl;
  27.     }
  28. }
  29.  
  30. void
  31. print_matrix2(int a[], int n)
  32. {
  33.     for (int i = 0; i < n; ++i) {
  34.         for (int j = 0; j < n; ++j) {
  35.             cout << a[n * i + j] << " ";
  36.         }
  37.         cout << endl;
  38.     }
  39. }
  40.  
  41. int
  42. main()
  43. {
  44.     srand(time(NULL));
  45.     int count;
  46.     cin >> count;
  47.     int n = (sqrt(8 * count + 1) - 1) / 2;
  48.     int a[count], b[count], c[n * n];
  49.     for (int i = 0; i < count; ++i) {
  50.         a[i] = rand() % 41 - 20;
  51.         b[i] = rand() % 41 - 20;
  52.     }
  53.     for (int i = 0; i < n; ++i) {
  54.         for (int j = 0; j < n; ++j) {
  55.             int tmp = 0;
  56.             for (int k = 0; k < n; ++k) {
  57.                 tmp += a[pos(n, i, k)] * b[pos(n, k, j)];
  58.             }
  59.             c[n * i + j] = tmp;
  60.         }
  61.     }
  62.     cout << "A:" << endl;
  63.     print_matrix1(a, n);
  64.     cout << "B:" << endl;
  65.     print_matrix1(b, n);
  66.     cout << "C:" << endl;
  67.     print_matrix2(c, n);
  68. }
Success #stdin #stdout 0s 2904KB
comments (?)
stdin 
6
stdout 
A:
11 -5 14 
-5 19 4 
14 4 15 
B:
16 -5 4 
-5 -4 9 
4 9 16 
C:
257 91 223 
-159 -15 215 
264 49 332
https://ideone.com/adRU5x
language:
C++14 (gcc 8.3)
created:
12 years ago
visibility:
public

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