Weighted Uniform Strings

Data Structures & Algorithms 2nd Semester

A weighted string is a string of lowercase English letters where each letter has a weight. Character weights are to from to as shown below:

The weight of a string is the sum of the weights of its characters. For example:
A uniform string consists of a single character repeated zero or more times. For example, ccc and a are uniform strings, but bcb and cd are not.

Given a string, , let be the set of weights for all possible uniform contiguous substrings of string . There will be queries to answer where each query consists of a single integer. Create a return array where for each query, the value is Yes if . Otherwise, append No.

Note: The symbol denotes that is an element of set .

Example

.

Working from left to right, weights that exist are:

string  weight
a       1
b       2
bb      4
c       3
cc      6
ccc     9
d       4
dd      8
ddd     12
dddd    16

Now for each value in , see if it exists in the possible string weights. The return array is ['Yes', 'No', 'No', 'Yes', 'No'].

Function Description

Complete the weightedUniformStrings function in the editor below.

weightedUniformStrings has the following parameter(s):
- string s: a string
- int queries[n]: an array of integers

Returns
- string[n]: an array of strings that answer the queries

Input Format

The first line contains a string , the original string.
The second line contains an integer , the number of queries.
Each of the next lines contains an integer , the weight of a uniform subtring of that may or may not exist.

Constraints

will only contain lowercase English letters, ascii[a-z].

Sample Input 0

abccddde
6
1
3
12
5
9
10

Sample Output 0

Yes
Yes
Yes
Yes
No
No

Explanation 0

The weights of every possible uniform substring in the string abccddde are shown below:

We print Yes on the first four lines because the first four queries match weights of uniform substrings of . We print No for the last two queries because there are no uniform substrings in that have those weights.

Note that while de is a substring of that would have a weight of , it is not a uniform substring.

Note that we are only dealing with contiguous substrings. So ccc is not a substring of the string ccxxc.

Sample Input 1

aaabbbbcccddd
5
9
7
8
12
5

Sample Output 1

Yes
No
Yes
Yes
No

solution

#include <bits/stdc++.h>

using namespace std;

string ltrim(const string &);
string rtrim(const string &);

/*
 * Complete the 'weightedUniformStrings' function below.
 *
 * The function is expected to return a STRING_ARRAY.
 * The function accepts following parameters:
 *  1. STRING s
 *  2. INTEGER_ARRAY queries
 */

vector<string> weightedUniformStrings(string input, vector<int> queries) {
    unordered_set<int> weights;
    int currentWeight = 0;
    char previousChar = '\0';

    for (char currentChar : input) {
        int charWeight = currentChar - 'a' + 1;
        if (currentChar == previousChar) {
            currentWeight += charWeight;
        } else {
            currentWeight = charWeight;
            previousChar = currentChar;
        }
        weights.insert(currentWeight);
    }

    vector<string> result;
    for (int queryWeight : queries) {
        if (weights.count(queryWeight)) {
            result.push_back("Yes");
        } else {
            result.push_back("No");
        }
    }

    return result;
}

int main()
{
    ofstream fout(getenv("OUTPUT_PATH"));

    string s;
    getline(cin, s);

    string queries_count_temp;
    getline(cin, queries_count_temp);

    int queries_count = stoi(ltrim(rtrim(queries_count_temp)));

    vector<int> queries(queries_count);

    for (int i = 0; i < queries_count; i++) {
        string queries_item_temp;
        getline(cin, queries_item_temp);

        int queries_item = stoi(ltrim(rtrim(queries_item_temp)));

        queries[i] = queries_item;
    }

    vector<string> result = weightedUniformStrings(s, queries);

    for (size_t i = 0; i < result.size(); i++) {
        fout << result[i];

        if (i != result.size() - 1) {
            fout << "\n";
        }
    }

    fout << "\n";

    fout.close();

    return 0;
}

string ltrim(const string &str) {
    string s(str);

    s.erase(
        s.begin(),
        find_if(s.begin(), s.end(), not1(ptr_fun<int, int>(isspace)))
    );

    return s;
}

string rtrim(const string &str) {
    string s(str);

    s.erase(
        find_if(s.rbegin(), s.rend(), not1(ptr_fun<int, int>(isspace))).base(),
        s.end()
    );

    return s;
}