[微软面试题]二进制加法

Implement a function that performs binary addition. Input to the function is two const strings. The function returns a string that holds the result of addition.
char* binaryadd(const char* a, const char* b) { }
Eg. "1001"+"101"="1110"

char* binaryadd(const char* a, const char* b)
{
    int nA;
    sscanf(a, "%d", &nA);
    int nB;
    sscanf(b, "%d", &nB);

    char tmp[32] = {0};
    itoa(nA+nB, tmp, 10);

    int nResult = 0;
    int nLenth = strlen(tmp);
    for(int i=nLenth-1,j=0; i>=0; i--)
    {
        if(tmp[i] == '1')
            nResult += 1<<j;
        else if(tmp[i] == '2')
            nResult += 1<<(j+1);
        j++;
    }

    char* sResult = new char[32];
    memset(sResult, 0, 32);
    itoa(nResult, sResult, 2);

    return sResult;
}

 

 

有好方法的同学不要客气哈！