Sum the number of times a digit appears in a sequence
By Peter Bromberg
This was a response to my Google+ LINQ Quiz:
Write a LINQ query that provides the sum of the number of times "1" is found in the sequence 1...100.
The answer is:
var sum = Enumerable.Range(1, 100).Sum(i => i.ToString().Count(c => c == '1'));
Sum the number of times a digit appears in a sequence (1231 Views)