题解 | #最长公共子串#
最长公共子串
https://www.nowcoder.com/practice/f33f5adc55f444baa0e0ca87ad8a6aac
package main
/**
* 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
*
* longest common substring
* @param str1 string字符串 the string
* @param str2 string字符串 the string
* @return string字符串
*/
func LCS(str1 string, str2 string) string {
m, n := len(str1), len(str2)
if m == 0 || n == 0 {
return ""
}
// 初始化dp数组
dp := make([][]int, m+1)
for i := range dp {
dp[i] = make([]int, n+1)
}
maxLength := 0
endIndex := 0
// 动态规划填表
for i := 1; i <= m; i++ {
for j := 1; j <= n; j++ {
if str1[i-1] == str2[j-1] {
dp[i][j] = dp[i-1][j-1] + 1
if dp[i][j] > maxLength {
maxLength = dp[i][j]
endIndex = i - 1
}
} else {
dp[i][j] = 0
}
}
}
// 返回最长公共子串
if maxLength > 0 {
return str1[endIndex-maxLength+1 : endIndex+1]
}
return ""
}
