Best Method for Sum Two Arrays

Best method for sum two arrays

a simple approach could be

$c = array_map(function () {
    return array_sum(func_get_args());
}, $a, $b);

print_r($c);

Or if you could use PHP5.6, you could also use variadic functions like this

$c = array_map(function (...$arrays) {
    return array_sum($arrays);
}, $a, $b);

print_r($c);

Output

Array
(
    [0] => 11
    [1] => 22
    [2] => 16
    [3] => 18
    [4] => 3
)

Sum two arrays in single iteration

I know this is an old question but I was just discussing this with someone and we came up with another solution. You still need a loop but you can accomplish this with the Array.prototype.map().

var array1 = [1,2,3,4];
var array2 = [5,6,7,8];

var sum = array1.map(function (num, idx) {
  return num + array2[idx];
}); // [6,8,10,12]

How to sum two arrays in another array in C?

What do you exactly want? Summation of each element from two arrays into a new third array? That's it right?

int main(int argc, char** argv) {
    int v1[3],v2[3],v3[3];

    for(int i  = 0 ; i < 3; i++) {
      printf("Type a number for v1 :\t");
      scanf("%d", &v1[i]);

      printf("Type a number for v2 :\t");
      scanf("%d", &v2[i]);
      // Add here
      v3[i] = v1[i] + v2[i]; // Mind you that this could lead to integer overflow.
  }

  printf("\nResult Arr :\n");
  for(int i  = 0 ; i < 3; i++)
    printf("%d\n", v3[i]);
}

Find the sum of two arrays

Well, all other answers are awesome for adding 2 numbers (list of digits).

But in case you want to create a program which can deal with any number of 'numbers',

Here's what you can do...

def addNums(lst1, lst2, *args):
    numsIters = [iter(num[::-1]) for num in [lst1, lst2] + list(args)]  # make the iterators for each list
    carry, final = 0, []                                                # Initially carry is 0, 'final' will store the result
    
    while True:
        nums = [next(num, None) for num in numsIters]                   # for every num in numIters, get the next element if exists, else None
        if all(nxt is None for nxt in nums): break                      # If all numIters returned None, it means all numbers have exhausted, hence break from the loop
        nums = [(0 if num is None else num) for num in nums]            # Convert all 'None' to '0'
        digit = sum(nums) + carry                                       # Sum up all digits and carry
        final.append(digit % 10)                                        # Insert the 'ones' digit of result into final list
        carry = digit // 10                                             # get the 'tens' digit and update it to carry

    if carry: final.append(carry)                                       # If carry is non-zero, insert it
    return final[::-1]                                                  # return the fully generated final list

print(addNums([6, 9, 8], [5, 9, 2]))                                    # [1, 2, 9, 0]
print(addNums([7, 6, 9, 8, 8], [5, 9, 2], [3, 5, 1, 7, 4]))             # [1, 1, 2, 7, 5, 4]

Hope that makes sense!

php, sum two array values

You can use array_keys to get the unique from both of the array and then loop through keys to some them

$r = [];
$keys = array_keys($a1+$a2);
foreach($keys as $v){
  $r[$v] = (empty($a1[$v]) ? 0 : $a1[$v]) + (empty($a2[$v]) ? 0 : $a2[$v]);
}

Working DEMO

How do I sum the respective elements of two arrays into another array in Javascript?

Use Array.map (see MDN)

const arr1 = [1, 2, 3, 4];
const arr2 = [2, 3, 4, 5];
const sums = arr1.map((v, i) => v + arr2[i]);
document.querySelector('#result').textContent = JSON.stringify(sums);

<pre id="result"></pre>

for (int i = 0; i < 10; i++) std::cout << A[i] + B[i] << "\n";