## Algorithm

Problem Name: 791. Custom Sort String

You are given two strings order and s. All the characters of `order` are unique and were sorted in some custom order previously.

Permute the characters of `s` so that they match the order that `order` was sorted. More specifically, if a character `x` occurs before a character `y` in `order`, then `x` should occur before `y` in the permuted string.

Return any permutation of `s` that satisfies this property.

Example 1:

```Input: order = "cba", s = "abcd"
Explanation:
"a", "b", "c" appear in order, so the order of "a", "b", "c" should be "c", "b", and "a".
Since "d" does not appear in order, it can be at any position in the returned string. "dcba", "cdba", "cbda" are also valid outputs.
```

Example 2:

```Input: order = "cbafg", s = "abcd"
```

Constraints:

• `1 <= order.length <= 26`
• `1 <= s.length <= 200`
• `order` and `s` consist of lowercase English letters.
• All the characters of `order` are unique.

## Code Examples

### #1 Code Example with C++ Programming

```Code - C++ Programming```

``````
class Solution {
public:
string customSortString(string S, string T) {
string res = "";
vectorv(26);
for(auto c: T) v[c - 'a']++;
for(auto c: S)
while(v[c - 'a']--) res.push_back(c);
for(int i = 0; i < 26; i++)
while(v[i]-- > 0) res.push_back('a' + i);
return res;
}
};
``````
Copy The Code &

Input

cmd
order = "cba", s = "abcd"

Output

cmd

### #2 Code Example with Java Programming

```Code - Java Programming```

``````
class Solution {
public String customSortString(String order, String s) {
Map frequency = new HashMap<>();
for (char c : s.toCharArray()) {
frequency.put(c, frequency.getOrDefault(c, 0) + 1);
}
StringBuilder sb = new StringBuilder();
for (char c : order.toCharArray()) {
int count = frequency.getOrDefault(c, 0);
while (count-- > 0) {
sb.append(c);
}
frequency.put(c, 0);
}
for (Character key : frequency.keySet()) {
int count = frequency.getOrDefault(key, 0);
while (count-- > 0) {
sb.append(key);
}
}
return sb.toString();
}
}
``````
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Input

cmd
order = "cba", s = "abcd"

Output

cmd

### #3 Code Example with Javascript Programming

```Code - Javascript Programming```

``````
const customSortString = function(S, T) {
const arr = [];
const remaining = [];
const hash = {};
for (let i = 0; i < S.length; i++) {
if (T.indexOf(S.charAt(i)) !== -1) {
arr.push(S.charAt(i));
}
}
let char;
for (let j = 0; j < T.length; j++) {
char = T.charAt(j);
if (arr.indexOf(char) === -1 && remaining.indexOf(char) === -1) {
remaining.push(char);
}
hash[char] = hash.hasOwnProperty(char) ? hash[char] + 1 : 1;
}
return `\${genPart(arr, hash)}\${genPart(remaining, hash)}`;
};

function constructStr(char, num) {
let str = "";
for (let i = 0; i < num; i++) {
str += char;
}
return str;
}

function genPart(arr, hash) {
return arr.reduce((ac, el) => {
return ac + constructStr(el, hash[el]);
}, "");
}

console.log(customSortString("kqep", "pekeq"));
console.log(
customSortString(
"hucw",
"utzoampdgkalexslxoqfkdjoczajxtuhqyxvlfatmptqdsochtdzgypsfkgqwbgqbcamdqnqztaqhqanirikahtmalzqjjxtqfnh"
)
);
``````
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Input

cmd
order = "cbafg", s = "abcd"

Output

cmd

### #4 Code Example with Python Programming

```Code - Python Programming```

``````
class Solution:
def customSortString(self, S, T):
"""
:type S: str
:type T: str
:rtype: str
"""
t = set(T)
t2 = set(S)
from collections import Counter as ct
c = ct(T)
s = [char * c[char] for char in S if char in t]
add = [char * c[char] for char in t - t2]
``````
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Input

cmd
order = "cbafg", s = "abcd"

Output

cmd

### #5 Code Example with C# Programming

```Code - C# Programming```

``````
using System.Text;

namespace LeetCode
{
public class _0791_CustomSortString
{
public string CustomSortString(string S, string T)
{
var counts = new int;
foreach (var ch in T)
counts[ch - 'a']++;

var sb = new StringBuilder();
foreach (var ch in S)
{
sb.Append(ch, counts[ch - 'a']);
counts[ch - 'a'] = 0;
}

for (char ch = 'a'; ch <= 'z'; ch++)
sb.Append(ch, counts[ch - 'a']);

return sb.ToString();
}
}
}
``````
Copy The Code &

Input

cmd
order = "cba", s = "abcd"

Output

cmd