我该如何解决“使用移动值”和“未实现“复制”特征的问题”？

Question

我正在尝试从向量中读取值，并将这些值用作索引以执行加法运算：

fn main() {
    let objetive = 3126.59;

    // 27
    let values: Vec<f64> = vec![
        2817.42, 2162.17, 3756.57, 2817.42, -2817.42, 946.9, 2817.42, 964.42, 795.43, 3756.57,
        139.34, 903.58, -3756.57, 939.14, 828.04, 1120.04, 604.03, 3354.74, 2748.06, 1470.8,
        4695.71, 71.11, 2391.48, 331.29, 1214.69, 863.52, 7810.01,
    ];

    let values_number = values.len();
    let values_index_max = values_number - 1;

    let mut additions: Vec<usize> = vec![0];

    println!("{:?}", values_number);

    while additions.len() > 0 {
        let mut addition: f64 = 0.0;
        let mut saltar: i32 = 0;

        // Sumar valores en additions
        for element_index in additions {
            let addition_aux = values[element_index];
            addition = addition_aux + addition;
        }
    }
}

我收到以下错误。我该如何解决？

fn main() {
    let objetive = 3126.59;

    // 27
    let values: Vec<f64> = vec![
        2817.42, 2162.17, 3756.57, 2817.42, -2817.42, 946.9, 2817.42, 964.42, 795.43, 3756.57,
        139.34, 903.58, -3756.57, 939.14, 828.04, 1120.04, 604.03, 3354.74, 2748.06, 1470.8,
        4695.71, 71.11, 2391.48, 331.29, 1214.69, 863.52, 7810.01,
    ];

    let values_number = values.len();
    let values_index_max = values_number - 1;

    let mut additions: Vec<usize> = vec![0];

    println!("{:?}", values_number);

    while additions.len() > 0 {
        let mut addition: f64 = 0.0;
        let mut saltar: i32 = 0;

        // Sumar valores en additions
        for element_index in additions {
            let addition_aux = values[element_index];
            addition = addition_aux + addition;
        }
    }
}

Answer 1

这个特定问题的解决方法是借用了Vec你遍历而不是移动：

for element_index in &additions {
    let addition_aux = values[*element_index];
    addition = addition_aux + addition;
}

但是您的代码还有其他问题。您永远不会additions通过添加或删除元素来进行更改，因此您while additions.len() > 0永远都不会终止。我希望这是因为您还没有完成，并想在编写其余函数之前先解决如何解决紧迫的问题。

现在，您可能会受益于重新阅读Rust Book中有关所有权，移动和借用的章节。