Decompose text to valid words (Word breaking)

Given a dictionary of valid words and an input text, write a function to check if the input text can be decomposed into valid words from dictionary.
Hint 1: use dynamic programming technique.
Hint 2: define T[k] is true if text[0...k] can be decomposed into valid words
Hint 3: T[k] is true if there exists any j : 0..k-1 where T[j] is true and text[j..k] is a valid word in dictionary.
This hints help us to write a simple loop to get the answer.

static string dic[4]={"bed","bath","beyond","and"};

bool decomps(string txt)
{
 map<string,bool> dm;
 for(int i=0;i<4;i++)
  dm[dic[i]]=true;
 vector<bool> t(txt.size()+1,false);
 t[0]=true;
 for(int k=1;k<=txt.size();k++)
 {
  bool candecomp=false;
  for(int i=0;i<k;i++)
  {
   string srch=txt.substr(i,k-i);
   map<string,bool>::iterator f=dm.find(srch);
   if(t[i]==true && f!=dm.end())
   {
    t[k]=true;
    break;
   }
  }
 }
 return t[txt.size()];
}
void  test_decomp()
{
 cout << decomps("bedbathandbeyond");
}