请问这几句JAVA代码如何转换成C++代码？
returnValue = Integer.toHexString(accumulator).toUpperCase();
for (i=returnValue.length(); i<4; i++)
returnValue = '0' + returnValue;

C++无法获得数组的长度啊

[解决办法]
用C写的。

C/C++ code

char* g(unsigned int a) {    char k[] = "0123456789ABCDEF";    char r[sizeof (a)*2];    int i = 0;    while (a != 0) {        r[i++] = k[a % 16];        a /= 16;    }    while (i < 4) {        r[i++] = '0';    }    char* t = malloc(i + 1);    int j = 0;    while (j < i) {        t[j++] = r[i - 1 - j];    }    t[i] = 0;    return t;}