C++ แปลงอักขระโรมัน

char ch[30];
int sum = 0;
int m, d, c, l, x, v, i;
m = d = c = l = x = v = i = 0;
cout << "Input : ";
cin >> ch;

for (int j = 0; j<strlen(ch); j++)
{
if (ch[j] == 'M')
{
m += 1000;
}
if (ch[j] == 'D')
{
d += 500;
}
if (ch[j] == 'C')
{
c += 100;
}
if (ch[j] == 'L')
{
l += 50;
}
if (ch[j] == 'X')
{
x += 10;
}
if (ch[j] == 'V')
{
v += 5;
}
if (ch[j] == 'I')
{
i += 1;
}
sum = m + d + c + l + x + v + i;
}
cout << endl;
cout << sum << endl;