Problem 1

 1sum = 0;
 2i = 0;
 3loop do
 4    if i == 1000
 5        break
 6    end
 7    if i % 3 == 0 || i % 5 == 0
 8        sum += i
 9    end
10    i += 1
11end
12puts "#{sum}"

 1(ns problem1.core)
 2
 3(defn mod3or5?
 4  [x]
 5  (cond
 6    (= (mod x 3) 0) x
 7    (= (mod x 5) 0) x
 8    :else 0))
 9
10(defn -main 
11  []
12   (println (reduce + (map mod3or5? (range 1 1000)) )))

1say [+] ( 1 .. ^ 1000 ).grep({ !($_ % ( 3 & 5 ))});

 1class SumMod3or5 {
 2    public static void main(String args[]){
 3        int UpperBound = 1000;
 4        int sum = 0;
 5        for(int i = 3; i < UpperBound; i++){
 6            if(i % 3 == 0 || i % 5 == 0){
 7                sum += i;
 8            }
 9        }
10        System.out.printf("%d\n", sum);
11    }
12}