fibonacci.java

public static int fibonacci(int n){
        int Un = 0;
        int Un1 = 1;
        int Un2 = 1;
        int temp = 0;

        for(int i = 0; i <= n; i++) {
            if(i == 0) {
                temp = 0;
            }

            if(i == 1) {
                temp = 1;
            }

            else {
                Un2 = Un1;
                Un1 = Un;
                Un = Un2 + Un1;
                temp = Un;
            }
        }
        return temp;
    }