我在进行编码练习时不知所措,我找不到正确的代码。
我需要从已排序的数组中删除重复项,而无需创建新数组。
基本上,我需要打开这个数组:
1 1 2 2 3 3 4 4 5 5 6 6 6 7 7
对此:
1 2 3 4 5 6 7 0 0 0 0 0 0 0 0
我的代码:
//show original array
int[] numbers = new int[] {1, 1, 2, 2, 2, 3, 4, 4, 5, 5, 6, 6, 6, 7, 7};
for (int counter = 0; counter < 15; counter++)
{
Console.Write(numbers[counter] + " ");
}
Console.WriteLine();
//remove the duplicates
for (int counter = 0; counter < (15 - 1); counter++)
{
???
}
//show updated array
for (int counter = 0; counter < 15; counter++)
{
Console.Write(numbers[counter] + " ");
}
Console.ReadLine();
答案 0 :(得分:0)
我又去了一次,因为我有强迫症,现在是喝咖啡的时间
如前所述,在特殊情况下
不能使用原始格式i + 1 == j && numbers[i] != numbers[j]
p.s感谢@EricLippert进行代码审查和实际测试。
int[] numbers = new int[] { 1, 2, 3, 4, 5, 5, 6, 6, 6, 7, 8, 9, 10, 10, 11, 12, 12, 14, 14 };
// i = unique = 0
// j = array index = 1
for (int i = 0, j = 1; j < numbers.Length; j++)
{
// if i and j are different we can move our unique index
if (numbers[i] != numbers[j])
if (++i == j) // special case, lets move on ++i
continue; // note we don't want to zero out numbers[j], so just continue
else
numbers[i] = numbers[j];
// wipe the guff
numbers[j] = 0;
}
Console.WriteLine(string.Join(",", numbers));
输出
1,2,3,4,5,6,7,8,9,10,11,12,14,0,0,0,0,0,0
就像
一样简单for (int i = 0, j = 1; j < numbers.Length; numbers[j++] = 0)
if(numbers[i] != numbers[j])
numbers[++i] = numbers[j];
输出
1,2,3,4,5,6,7,0,0,0,0,0,0,0,0
或者一个没有花哨的可读性更强的解决方案
for (int i = 0, j = 1; j < numbers.Length;j++ )
{
// is the last unique different from the current array index
if (numbers[i] != numbers[j])
{
// increment the last unique, so we don't overwrite it
i++;
// add the unique number at the next logical place
numbers[i] = numbers[j];
}
// wipe the guff
numbers[j] = 0;
}
基本上,这个想法是沿着数组移动,并保留最后一个唯一数字的索引