Question

How to declare and initialize 2D (two dimensional) int array in C

Answer 1

#include <stdio.h>
 
int main(void)
{
    int arr[5][3] = { 
                    { 1 }, 
                    { 0, 1 }, 
                    { [2] = 13 }, 
                    };             
    
    for (int i = 0; i < 5; i++)
    {
        for (int j = 0; j < 3; j++)
            printf("%d ", arr[i][j]);
        printf("\n");
    }
    
    return 0;
}

 
/*
run:

1 0 0
0 1 0
0 0 13
0 0 0
0 0 0

*/

 

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Answer 2

#include <stdio.h>
 
int main(void)
{
    int arr[5][3] = {1, 3, 5, 2, 4, 6, 8, 7};
    
    for (int i = 0; i < 5; i++)
    {
        for (int j = 0; j < 3; j++)
            printf("%d ", arr[i][j]);
        printf("\n");
    }
    
    return 0;
}

 
/*
run:

1 3 5
2 4 6
8 7 0
0 0 0
0 0 0

*/

 

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Answer 3

#include <stdio.h>
 
int main(void)
{
    int arr[5][3] = {{1, 3, 5}, {2, 6, 8}, {4, 9}};
    
    for (int i = 0; i < 5; i++)
    {
        for (int j = 0; j < 3; j++)
            printf("%d ", arr[i][j]);
        printf("\n");
    }
    
    return 0;
}

 
/*
run:

1 3 5
2 6 8
4 9 0
0 0 0
0 0 0

*/

 

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Answer 4

#include <stdio.h>
 
int main(void)
{
    int arr[5][3] = {[0][0] = 13, [1][1] = 90, [2][0] = 11};
    
    for (int i = 0; i < 5; i++)
    {
        for (int j = 0; j < 3; j++)
            printf("%d ", arr[i][j]);
        printf("\n");
    }
    
    return 0;
}

 
/*
run:

13 0 0
0 90 0
11 0 0
0 0 0
0 0 0

*/

 

Cleaner teeth, healthier you!
Get The Secret to a Bright and Healthy Smile