I have two arrays of char: a,b. How can i create with a loop "for" the new array vet, which is the union of the two alternating array a, b?

#include <stdio.h>

int main(void) {
    char a[] = "BNSIO";
    char b[] = "EISM\a";
    char vet[sizeof(a) + sizeof(b)];
    for (int i = 0; i < (sizeof(a) + sizeof(b)); i++) {

    }
    for (int i = 0; i < (sizeof(a) + sizeof(b)); i++){
        printf("%c", vet[i]);
    }
}

For alternating values from both arrays, try this (assuming lengths are equal):

int main()
{
    int i;
    char a[] = "BNSIO";
    char b[] = "EISM\a";
    char vet[sizeof(a) + sizeof(b)];

    for( i = 0; i < sizeof(a); i++) {
        vet[2*i] = a[i];
        vet[2*i+1] = b[i];
    }

    for(i = 0; i < sizeof(vet) ; i++){
        printf("%c", vet[i]);
    }
}

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