#include <iostream>
#include <stdio.h>
using namespace std;

#define M 0
#define D 1
#define C 2
#define L 3
#define X 4
#define V 5
#define I 6

int value[] ={ 1000, 500, 100, 50, 10, 5, 1 };
int rep[] = {-1,1,3,1,3,1,3};
int conv(char z) {
	switch (z) {
	case 	'm': return M;
case 		'd': return D;
case 		'c': return C;
case 		'l': return L;
case 		'x':return X;
case 		'v': return V;
case 		'i': return I;
	}
	return -1;
}

struct node {
	int v;
	node *next[7];
};
node root;
int test(int z, int z2) {
			if (z == D && z2 == M) 
				return -1;
			if (z == C && z2 == M) 
				return -1;
			if (z == L && (z2 == M || z2 == D || z2 == C)) 
				return -1;
			if (z == X && (z2 == M || z2 == D)) 
				return -1;
			if (z == V && (z2 == M || z2 == D || z2 == C)) 
				return -1;
			if (z == V && (z2 == L || z2 == X)) 
				return -1;
			if (z == I && (z2 == M || z2 == D || z2 == C)) 
				return -1;
			if (z == I && (z2 == L)) 
				return -1;

	return 0;
}
int num(string s) {
	int t;
	int v = 0;
	int z,z2;
	int l = (int)s.length()-1;

	char p = -1;
	int num;
	for (t=0;t<(l+1);t++) {
		z = conv(s[t]);	
		if (z !=p) {
			num = 1;
			p = z;
		}
		else  {
			num++;
			if (rep[z] == -1) 
				continue;
			if (rep[z] < num)
				return -1;
		}
	}
	
	t = 0;
	while (t<=l) {
		z = conv(s[t]);
		if (t!=l) {

			z2 = conv(s[t+1]);
			if (test(z,z2) == -1) 
				return -1;
			if (z>z2) {
				if (t!=0) {
					int a;
					a = conv(s[t-1]);
					if(a==z)
						return -1;
				}
				v += (value[z2]-value[z]);
				if ((t+1)!=l) {
					z =z2;
					z2 = conv(s[t+2]);
					if (test(z,z2) == -1) 
						return -1;
				}
				t+=2;
			} else {
				v += value[z];
				t++;
			}
		
		} else  {
			v += value[z];
			t++;
		}
	}
        	
	return v;
}

string get_string(string s) {
	int t;
	string x;
	for (t=0;t<(int)s.length();t++) {
		if (conv(s[t]) != -1) {
			x += s[t];	
		}
	}
	return x;
}
long int getb(long int x,int m) {
	long int msk = (1 << m);
	return (x & msk);
}

void init_node(node *n) {
	n->v = -2;
	int t;
	for (t=0;t<7;t++) {
		n->next[t] = NULL;
	}
}

void compute(string s) {
	long int c=1;
	long int t;
	int l = (int)s.length();
	char m[1000];
	int max = 0;
	for (t=0;t<l;t++)
		c*=2;	
	for (t=1;t<c;t++) {
		int z;
		int xx = 0;
		for (z=0;z<l;z++) {
			if (getb(t,z)) {
				m[xx]=s[z];	
				xx++;
			}
		}
		m[xx] = 0;
	
		int hn = 0; /// SEARCH
		node *n = &root;
		bool found = true;
		while (hn!=xx) {
			int v = conv(m[hn]);
			if (n->next[v] == NULL) {
				found = false;
				n->next[v] = new node;
				init_node(n->next[v]);
			}
			n = n->next[v];
			hn++;
		}
		int zzz;
		if (found) {
			if (n->v == -2)
			{
				zzz = num(m);
				n->v = zzz;
			}
			else  {
				zzz = n->v;

				
			}
		} else {
			zzz = num(m);
			n->v = zzz;

		}
//		cout << t << "   " << m << "   " << num(m) << endl;

		if (max < zzz) 
			max = zzz;
	}
	cout << max << endl;
	
}

string readline() {
	string s;
	char c;
	c = getc(stdin);
	while (c != '\n'){
		s += c;
		c = getc(stdin);
	}
	return s;
}

int main() {
/*	string s = get_string("metfyz is the best school in prague");
	cout << s<< endl;
	compute(s);*/
/*	string s = get_string("no year");
	cout << s<< endl;
	compute(s);*/
	string s;
	init_node(&root);
	s  = readline();
	while (s != "") {
	 	compute(get_string(s));		
//	 	cout << s << endl;
		s = readline();
	}

/*	printf("%i\n",num("CII"));		
	printf("%i\n",num("XCIX"));		
	printf("%i\n",num("CXX"));		
	printf("%i\n",num("LII"));		
	printf("%i\n",num("IX"));		
	printf("%i\n",num("VII"));		
	printf("%i\n",num("MMMCDXLIX"));		
	
	printf("%i\n",num("IC"));		
	printf("%i\n",num("IIC"));		
	printf("%i\n",num("VX"));		
	printf("%i\n",num("IM"));		
	printf("%i\n",num("MIIII"));		
	printf("%i\n",num("MDD"));		
	printf("%i\n",num("XVV"));		
	printf("%i\n",num("IXM"));		

	printf("%i\n",num("xcx"));		*/
}