Java Language
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Java Language Recursion Computing the sum of integers from 1 to N
Example
The following method computes the sum of integers from 0 to N using recursion.
public int sum(final int n) {
if (n > 0) {
return n + sum(n - 1);
} else {
return n;
}
}
This method is O(N) and can be reduced to a simple loop using tail-call optimization. In fact there is a closed form expression that computes the sum in O(1) operations.
