所有偶数Fibonacci数的总和

Question

我试图得到所有偶数斐波纳契数的总和.我可以打印出数字,但我无法得到它们的总和.这是在java中.

class driver {
    public static void main(String [] args) {
        int a; 
        int b = 0;
        int c = 1;

        for (int i = 0; i < 10; i++) { // Finds fibonacci sequence
            a = b;
            b = c;
            c = a + b;

            if ( c % 2 == 0) { // Check if it's even
                int sum = 0;
                sum = sum + c;
                System.out.println(sum);
            }
            else {

            }
        }
    }
}

Answer 1

你不应该sum在循环中每次重新初始化,因为这会导致它失去它所拥有的值.它的范围应该在其外部,if以便每次都可以增加相同的变量.

class driver {
    public static void main(String [] args) {
        int a; 
        int b = 0;
        int c = 1;
        int sum = 0;

        for (int i = 0; i < 10; i++) { // Finds fibonacci sequence
            a = b;
            b = c;
            c = a + b;

            if (c % 2 == 0)  // Check if it's even
                sum += c;
        }
        System.out.println(sum);
    }
}