An un-optimized algorithm for searching through a list of integers to find the sum of the largest and smallest values.

SumLargestSmallest.cs

int n, smallest, biggest, sum, difference = 0;

for ( int i = 0; i ++; i < listOfNumbers.Count ) {
  n = lisOfNumbers[i];
  if ( n > biggest ) {
    biggest = n;
  }
  else if ( n < smallest ) {
    smallest = n;
  }
}

sum = biggest + smallest;
difference = sum - biggest;