题解 | #最长公共子串#
最长公共子串
http://www.nowcoder.com/practice/f33f5adc55f444baa0e0ca87ad8a6aac
/**
* longest common substring
* @param str1 string字符串 the string
* @param str2 string字符串 the string
* @return string字符串
*/
function LCS( str1 , str2 ) {
// write code here
const arr1 = str1.split("")
const arr2 = str2.split("")
const strTemp = []
let str = ""
for( let i = 0, l1 = arr1.length; i < l1; i++ ) {
const item1 = arr1[i]
strTemp[i] = []
for( let j = 0, l2 = arr2.length; j < l2; j++ ) {
const item2 = arr2[j]
strTemp[i][j] = ""
if( item1 === item2 ) {
if(i > 0 && j > 0){
strTemp[i][j] = strTemp[i-1][j-1] ? strTemp[i-1][j-1] + item2 : item2 ;
}else {
strTemp[i][j] = item2;
}
if( strTemp[i][j].length > str.length ) {
str = strTemp[i][j]
}
}
}
}
return str
}
module.exports = {
LCS : LCS
};
