Longest Common String -Unefficient Way

 function removeChar(str, startIndex, toRemove) {

var newString = ""

for (let i = 0; i < str.length; i++) {

if (i >= startIndex && i < startIndex + toRemove) {

continue

} else {

newString = newString + str[i]

}

}

return newString

}

function GetAllCombinations(s1) {

var s1Word = new Set()

var lenofs1 = s1.length;

var visited = []

for (let i = 1; i < lenofs1; i++) {

for (let j = 0; j < lenofs1 - i + 1; j++) {

var str = removeChar(s1, j, i)

if (visited.includes(str) == false) {

visited.push(str)

//s1Word.add({ "string": str, "i": i, "j": j, "source": s1 })

s1Word.add(str)

if (str.length > 1) {

let rec = GetAllCombinations(str)

s1Word = new Set([...rec, ...s1Word])

}

}

}

}

return s1Word

}

function commonChild(s1, s2) {

let res1 = GetAllCombinations(s1)

const array1 = Array.from(res1);

var res2 = GetAllCombinations(s2)

const array2 = Array.from(res2);

var common = []

for (let i = 0; i < array1.length; i++) {

if (array2.includes(array1[i])) {

common.push(array1[i])

}

}

var maxLenth = Number.NEGATIVE_INFINITY

var maxStr = ""

for (let i = 0; i < common.length; i++) {

if (maxLenth < common[i].length) {

maxLenth = common[i].length

maxStr = common[i]

}

}

return maxStr.length

}

let s1 = "SHINCHAN", s2 = "NOHARAAA";

let res = commonChild(s1, s2)

console.log("Result", res)