Find the number of times the most-common substring occurs in a given string

findOccurrencesOfMostCommonSubstring.cpp

/* Given an input string of size n, return the number of occurrences
 * of the most common substring between lengths k,l.
 */
int findOccurrencesOfMostCommonSubstring(int n, int k, int l, const string &input)
{
    std::map<std::string, int> substringMap;
    int maxOccurrences = 1;
   
    // 1. Build every legal substring with lengths between k and l
    // 2. Place into map
    // 3. Increment count associated with the substring
    // 4. Determine if it is most common
    // 5. Return count for most common
    const int inputLen = input.size();

    // i serves as our left-bound for the substrings
    for (int i = 0; i < inputLen - 1; ++i) {
       
        // j serves as our right-bound for the substrings
        // 1. At each right-bound, create the longest legal substring that we can without
        //    walking past the end of the string.
        // 2. Insert it into the map.
        // 3. Update maxOccurrences
        // 4. When we're finished, return maxOccurrences.
        for (int j = k; j <= l && i + j <= inputLen; ++j) {
            const std::string current = input.substr(i,j);
           
            // DEBUG
            // std::cout << "("<< i << "," << j << ") : " << current << std::endl;
           
            // If 'current' isn't in the map, it will insert a value
            // of 0. This means we can simply increment currentValue
            // regardless of it being present in the map or not,
            // and we'll achieve correct behavior in both cases.
            int &currentValue = substringMap[current];
           
            maxOccurrences =
                    (++currentValue > maxOccurrences)
                    ? currentValue : maxOccurrences;
        }
    }

    return maxOccurrences;
}

@zachelko - Line 25 should be
for (int j = k; j <= l && j <= inputLen; ++j) {