Question

我的任务：输入是一维数组。必须找到最大宽度的范围，该范围的元素为正（大于0）。作为响应，应该有2个元素组成的数组，其中： -元素编号0-段左边界的索引元素； -元素№1-段右边界元素的索引。

如果有多个这样的段，则返回RIGHT。如果数组中没有这样的段（所有数字均为负），则返回一个空数组。我不明白我做错了什么。有我的代码：

public class ArrayUtils {
public static int[] lookFor(int[] array) {
    int[] result = new int[2];
    int firstIndex = 0;
    int lastIndex = 0;
    int sequenceLength = 0;
    int currentSequenceLength = 0;

    for (int i = 0; i < array.length; i++) {
        if (array[i] > 0) {
            if ( currentSequenceLength == 0 ) {
                firstIndex = i;
            }

            currentSequenceLength += 1;
            lastIndex = i;
        } else {
    if (currentSequenceLength > sequenceLength) {
        sequenceLength = currentSequenceLength;
        result[0] = firstIndex;
        result[1] = lastIndex;
    }
            currentSequenceLength = 0;
        }
    }


    if (sequenceLength == 0) {
        return new int[0];
    }

    return result;
}

}

Answer 1

我看到两个问题：

if there are several such segments, return the RIGHT-这意味着即使长度相同，也应将前一个最长的序列替换为当前的最长序列。即if (currentSequenceLength > sequenceLength)应该是if (currentSequenceLength >= sequenceLength)。

您将忽略任何以数组的最后一个索引结尾的序列。您应该在循环后通过添加以下内容来处理它：

if (currentSequenceLength >= sequenceLength) {
    sequenceLength = currentSequenceLength;
    result[0] = firstIndex;
    result[1] = lastIndex;
}

总而言之，您的方法应如下所示：

public static int[] lookFor(int[] array) {
    int[] result = new int[2];
    int firstIndex = 0;
    int lastIndex = 0;
    int sequenceLength = 0;
    int currentSequenceLength = 0;

    for (int i = 0; i < array.length; i++) {
        if (array[i] > 0) {
            if ( currentSequenceLength == 0 ) {
                firstIndex = i;
            }

            currentSequenceLength += 1;
            lastIndex = i;
        } else {
            if (currentSequenceLength >= sequenceLength) {
                sequenceLength = currentSequenceLength;
                result[0] = firstIndex;
                result[1] = lastIndex;
            }
            currentSequenceLength = 0;
        }
    }
    if (currentSequenceLength >= sequenceLength) {
        sequenceLength = currentSequenceLength;
        result[0] = firstIndex;
        result[1] = lastIndex;
    }


    if (sequenceLength == 0) {
        return new int[0];
    }

    return result;
}

如何返回最右边的正数数组削减？

1 个答案: