动态规划—求最长字符串子序列

<pre name="code" class="cpp">void findMaxLCS(char *pStr,int nLen){    bool** pFlag = new bool* [nLen];    for (int index=0; index<nLen; index++) {        pFlag[index] = new bool[nLen];    }    for (int index=0; index<nLen; index++) {        pFlag[index][index] = true;    }        for (int nCurLen = 2; nCurLen<=nLen; nCurLen++)        for (int i=0; i<nLen-nCurLen+1; i++) {            int j=nCurLen+i-1;            if (nCurLen==2) {                pFlag[i][j] = (pStr[i]==pStr[j]);            }            else{                pFlag[i][j] = (pStr[i]==pStr[j]&&pFlag[i+1][j-1]);            }        }    int nMaxLen = 0;    int nStart = 0;    for (int i=0; i<nLen; i++) {        for (int j=0; j<nLen; j++) {            if (pFlag[i][j]&&(j-i)>nMaxLen) {                nMaxLen = j-i;                nStart = i;            }            std::cout<<pFlag[i][j];        }        std::cout<<std::endl;    }    for (int i=0; i<=nMaxLen; i++) {        std::cout<<pStr[nStart+i];    }    std::cout<<std::endl;}

char strA[] = "ahelloworld"; char strB[] = "ahwordabc"; int nLength = (int)strlen(strA); int nWidth = (int)strlen(strB); int nFlag[nLength+1][nWidth+1]; memset(nFlag, 0, sizeof(int)*(nLength+1)*(nWidth+1)); for (int i= 0; i<nLength; i++) { if (strA[i]==strB[0]) { nFlag[i][0] = 1; } } for (int i= 0; i<nLength; i++) { if (strA[0]==strB[i]) { nFlag[0][i] = 1; } } for (int i = 1; i<=nLength; i++) { for (int j = 1; j<=nWidth; j++) { if (strA[i]==strB[j]) { nFlag[i][j] = nFlag[i-1][j-1]+1; } else if (nFlag[i][j-1]>nFlag[i-1][j]){ nFlag[i][j] = nFlag[i][j-1]; } else{ nFlag[i][j] = nFlag[i-1][j]; } } } int i=1; int j=1; while (i<=nLength&&j<=nWidth) { if (nFlag[i][j]>nFlag[i-1][j-1]) { std::cout<<strA[i]<<","; i++; j++; } else if(nFlag[i][j]==nFlag[i-1][j]) { i++; } else{ j++; } } std::cout<< std::endl;