#include <iostream>
using namespace std;
int value(char r)
{
if (r == 'I')
return 1;
if (r == 'V')
return 5;
if (r == 'X')
return 10;
if (r == 'L')
return 50;
if (r == 'C')
return 100;
if (r == 'D')
return 500;
if (r == 'M')
return 1000;
return -1;
}
int romanToDecimal(string &str)
{
// Initialize result
int res = 0;
// Traverse given input
for (int i=0; i<str.length(); i++)
{
// Getting value of symbol s[i]
int s1 = value(str[i]);
if (i+1 < str.length())
{
// Getting value of symbol s[i+1]
int s2 = value(str[i+1]);
// Comparing both values
if (s1 >= s2)
{
// Value of current symbol is greater
// or equal to the next symbol
res = res + s1;
}
else
{
res = res + s2 - s1;
i++; // Value of current symbol is
// less than the next symbol
}
}
else
{
res = res + s1;
i++;
}
}
return res;
}
int main() {
string str;
getline(cin,str);
cout<<romanToDecimal(str);
return 0;
}
