excel表列名称#168

1 -> A
2 -> B
3 -> C
...
26 -> Z
27 -> AA
28 -> AB 
... 示例 1:

输入: 1
输出: "A" 示例 2:

输入: 28
输出: "AB" 示例 3:

输入: 701
输出: "ZY"

//C style
//65->A
char* convertToTitle(int n) {

    char *d = (char*)malloc(sizeof(char*) * 10);
    
    int i = 0;
    while(n > 0){
        int x = (n-1)%26;
        n = (n-1) / 26;
        d[i++] = x+'A';
    }
    char *a =  (char*)malloc(sizeof(char*) * 10);
    i = 0;
    int j = strlen(d) -1;
    while(j>=0) {
        a[i++] = d[j--];
    }
    return a;
}

 701 输出: 

"ZY"