Minimum number of coins to be added

#[test]
fn t1() {
    let start = std::time::Instant::now();
    let val = Solution::minimum_added_coins(vec![1, 4, 10], 19);
    let expected = 2;
    log_result!(val == expected, "t1", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn t2() {
    let start = std::time::Instant::now();
    let val = Solution::minimum_added_coins(vec![1, 4, 10, 5, 7, 19], 19);
    let expected = 1;
    log_result!(val == expected, "t2", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn t3() {
    let start = std::time::Instant::now();
    let val = Solution::minimum_added_coins(vec![1, 1, 1], 20);
    let expected = 3;
    log_result!(val == expected, "t3", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn t4() {
    let start = std::time::Instant::now();
    let val = Solution::minimum_added_coins(vec![2], 1);
    let expected = 1;
    log_result!(val == expected, "t4", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn t5() {
    let start = std::time::Instant::now();
    let val = Solution::minimum_added_coins(vec![1, 2, 3], 6);
    let expected = 0;
    log_result!(val == expected, "t5", start, &expected, &val);
    assert_eq!(val, expected);
}

#[test]
fn t6() {
    let start = std::time::Instant::now();
    let val = Solution::minimum_added_coins(vec![1], 7);
    let expected = 2;
    log_result!(val == expected, "t6", start, &expected, &val);
    assert_eq!(val, expected);
}