如何使用 C# 找到给定字符串中字符的最长距离?
csharpserver side programmingprogramming更新于 2025/4/18 10:37:17
创建 2 个不同的数组 leftDis 和 rightDis。leftDis 将存储从左侧移动时的值。rightDis 将存储从右侧移动时的最短值。每当遇到字符时，将字符的位置添加到数组中。在最后一步中，计算两个数组的最大值。
时间复杂度 − O(n)
空间复杂度 − O(n)
示例
public class Arrays{
public int[] LongestDistanceToCharacter(string s, char c){
int stringLength = s.Length;
int[] leftDis = new int[s.Length];
int[] rightDis = new int[s.Length];
leftDis = Enumerable.Range(0, s.Length).Select(n => int.MinValue).ToArray();
rightDis = Enumerable.Range(0, s.Length).Select(n => int.MaxValue).ToArray();
int count = int.MaxValue;
for (int i = 0; i < rightDis.Length; i++){
if (s[i] == c){
count = 0;
rightDis[i] = count;
}
else{
if (count != int.MaxValue){
count++;
rightDis[i] = count;
}
}
}
count = int.MaxValue;
for (int i = leftDis.Length - 1; i >= 0; i--){
if (s[i] == c){
count = 0;
leftDis[i] = count;
}
else{
if (count != int.MaxValue){
count++;
leftDis[i] = count;
}
}
}
int[] ans = new int[stringLength];
for (int i = 0; i < stringLength - 1; i++){
ans[i] = Math.Max(leftDis[i], rightDis[i]);
}
return ans;
}
}
static void Main(string[] args){
Arrays s = new Arrays();
string ss = "lovecode";
char c = 'e';
var res = s.LongestDistanceToCharacter(ss, c);
foreach (var item in res){
Console.WriteLine(item);
}
}
输出
[2147483647,2147483647,2147483647,0,3,2,3,0]
