Question

How to declare and initialize an array in C

Answer 1

#include <stdio.h>

int main(void) 
{
    int array[5] = {0};

    size_t size = sizeof(array) / sizeof(array[0]);
    
    for (int i = 0; i < size; i++)
        printf("%3d", array[i]);
    
    return 0;
}
   
/*
run:

  0  0  0  0  0

*/

 

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Answer 2

#include <stdio.h>

int main(void) 
{
    int array[5] = {1, 2, 3, 4, 5};

    size_t size = sizeof(array) / sizeof(array[0]);
    
    for (int i = 0; i < size; i++)
        printf("%3d", array[i]);
    
    return 0;
}
   
/*
run:

  1  2  3  4  5

*/

 

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Answer 3

#include <stdio.h>

int main(void) 
{
    int array[5] = {[2] = 98, [4] = 13, [1] = 37};

    size_t size = sizeof(array) / sizeof(array[0]);
    
    for (int i = 0; i < size; i++)
        printf("%3d", array[i]);
    
    return 0;
}
   
/*
run:

  0 37 98  0 13

*/

 

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Answer 4

#include <stdio.h>

int main(void) 
{
    int array[] = {[2] = 98, [5] = 13, [1] = 37};

    size_t size = sizeof(array) / sizeof(array[0]);
    
    for (int i = 0; i < size; i++)
        printf("%3d", array[i]);
    
    return 0;
}
   
/*
run:

  0 37 98  0  0 13

*/

 

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Answer 5

#include <stdio.h>

int main(void) 
{
    int array[] = {1, 2, 3, 98};

    size_t size = sizeof(array) / sizeof(array[0]);
    
    for (int i = 0; i < size; i++)
        printf("%3d", array[i]);
    
    return 0;
}
   
/*
run:

  1  2  3 98

*/

 

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