ワードブレイク問題

wordBreak(string, n, result)

入力- 与えられた文字列、文字列の長さ、分離された文字列。

出力- 辞書を使用して文字列を区切ります。

Begin
   for i := 0 to n, do
      subStr := substring of given string from (0..i)
      if subStr is in dictionary, then
         if i = n, then
            result := result + subStr
            display the result
            return
         wordBreak(substring from (i..n-i), n-i, result, subStr, ‘space’)
   done
End

例

#include <iostream>
#define N 13
using namespace std;

string dictionary[N] = {"mobile","samsung","sam","sung","man","mango", "icecream","and",
                        "go","i","love","ice","cream"};

int isInDict(string word){    //check whether the word is in dictionary or not
   for (int i = 0; i < N; i++)
      if (dictionary[i].compare(word) == 0)
         return true;
   return false;
}

void wordBreak(string str, int n, string result) {
   for (int i=1; i<=n; i++) {
      string subStr = str.substr(0, i);       //get string from 0 to ith location of the string
      if (isInDict(subStr)) {       //if subStr is found in the dictionary
         if (i == n) {
            result += subStr; //add substring in the result.
            cout << result << endl;
            return;
         }
         wordBreak(str.substr(i, n-i), n-i, result + subStr + " ");    //otherwise break rest part
      }
   }
}

int main() {
   string str="iloveicecreamandmango";
   wordBreak(str, str.size(),"");
}

出力

i love man go ice cream
i love man go icecream
i love mango ice cream
i love mango icecream