Open Qingquan-Li opened 2 years ago
Concept: A two-dimensional array is like several identical arrays put together. It is useful for storing multiple sets of data.
double array[Rows][Columns];
// Assigns the value 99.5 to the element at // row#2 column#1 of the scores array: scores[1][0] = 99.5;
#include <iostream> using namespace std; int main() { const int ROWS = 3; const int COLUMNS = 4; // The extra braces that enclose each row's initialization list // is optional. // int num_ppl[ROWS][COLUMNS] = { // 4, 5, 2, 3, 0, 0, 5, 5, 5, 4, 2, 0 // }; int num_ppl[ROWS][COLUMNS] = {{4, 5, 2, 3}, {0, 0, 5, 5}, {5, 4, 2, 0} }; for (int i = 0; i < ROWS; i++) { for (int j = 0; j < COLUMNS; j++) { cout << num_ppl[i][j] << " "; } cout << endl; } return 0; }
Output:
4 5 2 3 0 0 5 5 5 4 2 0
When a two-dimensional array is passed to a function, the parameter type must contain a size declarator for the number of columns.
Here is the header for the function print_2D_array below:
print_2D_array
void print_2D_array(int arr[][COLUMNS], int rows)
#include <iostream> using namespace std; const int COLUMNS = 4; // Function prototype: void print_2D_array(int[][COLUMNS], int); int main() { const int ROWS = 3; int num_ppl[ROWS][COLUMNS] = {{1, 2, 2, 3}, {0, 0, 5, 5}, {5, 4, 2, 0} }; print_2D_array(num_ppl, ROWS); return 0; } void print_2D_array(int arr[][COLUMNS], int rows) { for (int i = 0; i < rows; i++) { for (int j = 0; j < COLUMNS; j++) { cout << arr[i][j] << " "; } cout << endl; } }
1 2 2 3 0 0 5 5 5 4 2 0
1. Two-dimensional array initialization
Output:
2. Passing Two-Dimensional Arrays to Functions
When a two-dimensional array is passed to a function, the parameter type must contain a size declarator for the number of columns.
Here is the header for the function
print_2D_array
below:Output: