Two-Dimensional Arrays (Tabular Data)

This lesson covers using a two-dimensional array in C, so you can work with tabular data. It's for anyone searching "C 2D array usage."

Writing int grid[2][3] represents a "grid-like table" with rows and columns — called a two-dimensional array. Access it with grid[row][col].

The example declares data with 2 rows and 3 columns as {{1, 2, 3}, {4, 5, 6}}, and accesses an element using two stacked brackets, like grid[1][2]. Notice the nested for loop displaying the whole thing.

A common early mistake is not knowing how a two-dimensional array is actually laid out in memory. Even though it looks like a table on the surface, it's genuinely stored as one contiguous line of memory underneath — knowing this deepens your understanding.

In real projects, this idea gets applied to things like a game board with coordinates, or spreadsheet-like data.

📖 Reference code

#include <stdio.h>

int main(void) {
    int grid[2][3] = {
        {1, 2, 3},
        {4, 5, 6}
    };
    printf("%d\n", grid[1][2]);
    for (int i = 0; i < 2; i++) {
        for (int j = 0; j < 3; j++) {
            printf("%d", grid[i][j]);
            if (j < 2) printf(",");
        }
        printf("\n");
    }
    return 0;
}

✍️ Your code

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🧪 This site can't compile or run C directly, so it checks on the spot whether what you typed matches the reference code (scoring happens entirely in your browser — nothing is sent anywhere).