#include <stdio.h>
#include <stdlib.h>
#define maxn 30
int main()
{
char a[maxn];
while (scanf("%s",a)==1)
{
int b=0,i;
float s =0;
int c=strlen(a);
for (i=0;i<c;i++)
{
if (a[i]=='C')
{
if (a[i+1]>='1' && a[i+1]<='9'){
b=(a[i+1]-'0');
s+=12.01*b;}
else
s+=12.01;
}
if (a[i]=='H')
{
if (a[i+1]>='1' && a[i+1]<='9'){
b=(a[i+1]-'0');
s+=1.008*b;}
else
s+=1.008;
}
if (a[i]=='O')
{
if (a[i+1]>='1' && a[i+1]<='9'){
b=(a[i+1]-'0');
s+=16.00*b;}
else
s+=16.00;
}
if (a[i]=='N')
{
if (a[i+1]>='1' && a[i+1]<='9'){
b=(a[i+1]-'0');
s+=14.01*b;}
else
s+=14.01;
}
}
printf("%.3fg/mol",s);
}
return 0;
}
