Write a function:

INPUT: Array of integers (fixed size), size unknown but is multiple of 5
OUTPUT: ArrayList of integers

sum every 5 numbers
store each sum in and arraylist
return it

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1+2+3+4+5 ,   6+7+8+9+10 , 11+12+13+14+15

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ArrayList<Integer> sumThing (int [] nums){
    ArrayList<Integer> result = new ArrayList<Integer>();

   int index = 0;
   int sum;

   for(int j=0; j < nums.length / 5; j++){
      sum = 0;
      for(int i=0; i < 5; i++){
          sum += nums[i + index];
      }
      index += 5;
      result.add(sum);
   }

   return result;
}
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Solution Version 2: different but the same


ArrayList<Integer> sumThing (int [] nums){
    ArrayList<Integer> result = new ArrayList<Integer>();

   int sum = 0;
   int counter = 0;
   for(int i =0; i < nums.length; i++){
      counter++;
      sum += nums[i];
      if(counter == 5){
          result.add(sum);
          sum = 0;
          counter = 0;
      }
    
   }

   return result;
}



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Solution Version 3: different but the same




ArrayList<Integer> sumThing (int [] nums){
    ArrayList<Integer> result = new ArrayList<Integer>();

    int sum;

    for(int j = 0; j < nums.length; j += 5){
       sum = 0;
       for(int i = j; i < j+ 5; i++){
           sum += nums[i];
       }

       result.add(sum);

    }
   return result;
}


==============================================
Solution Version 4: different but the same



ArrayList<Integer> sumThing (int [] nums){
    ArrayList<Integer> result = new ArrayList<Integer>();

   int sum = 0;

   for(int i =0; i < nums.length; i++){
      sum += nums[i];
      if(i % 5 == 0){
          result.add(sum);
          sum = 0;
      }
    
   }

   return result;
}