Codeforces Round #376 (Div. 2)/A. Night at the Museum

Problem Link:http://codeforces.com/contest/731/problem/A
Code:

#include<bits/stdc++.h>
using namespace std;
#include<string.h>
//#include<math.h>
int main()
{
    char ch[200];
    int i,a,l,b,sum;
    while(cin>>ch)
    {
        l=strlen(ch);
        //a=ch[0]-96;
        sum=abs('a'-ch[0]);
        if(abs(26-sum)<sum)
            sum=26-sum;
        for(i=0;i<l-1;i++)
        {
           // cout<<ch[i]<<" "<<ch[i+1]<<endl;
            a=abs(ch[i]-ch[i+1]);
            b=abs(26-a);
            if(a>b)
                a=b;
            sum+=a;
            //cout<<"a="<<a<<endl;

        }
        cout<<sum<<endl;
    }
    return 0;
}