Count up and multiplied by 2

#include <stdio.h>

int main(void){

  int i;
  int data1[10],data2[10];

  for(i = 0;i<10;i++){
    data1[i] = i;
    printf("\n");
    data2[i] = data1[i] * 2;
    printf("%d",data2[i]);
  }

  return 0;
}
#include <stdio.h>

int main(void){

  char a[] = "a[]=";
  printf("%s",a);

  int i = 0;
  for(i;i<5;){
    a[i]= i*2;
    printf("%d",a[i]);
    i++;
  }

  return 0;
}