http://haixiaoyang.wordpress.com/category/dynamic-programming/
//Given a string and a function : bool IsWord(const char* szBeg, const char* szEnd), use this //function to judge whether the string can be split into seperate words. //for example : "thisisasentence" can be split into "this is a sentence" //pseudocode: bool IsWord(const char* szBeg, const char* szEnd); bool IsSplittable(const char* szString) { if (*pIter == '\0') return true; const char* pIter = szString; while (*pIter != '\0') { if (IsWord(szString, pIter) && IsSplittable(pIter+1)) return true; pIter++; } return false; } //DP version: bool Detect(char *str) { assert(str); int nNum = strlen(str); if (nNum == 0) return false; //pRec[i] means if the sentence from position i can be cut into words //do this backwards bool* pRec = new bool[nNum+1]; memset(pRec, 0, sizeof(bool)*nNum); pRec[nNum] = true; for (int i = nNum-1; i = 0; i--) { for (int j = i; j <= nNum-1; j++) { if (IsWord(&str[i], &str[j]) && pRec[j+1]) { pRec[i] = true; break; } } } bool bRet = pRec[0]; delete []pRec; return bRet; }
这个题目在实际工程中经常遇到,通常的做法是把问题转化成图问题,在图中寻找路径。