Lawn mower (UVALive 4954, UVA 12269, Regionals 2010 >> Europe - Southwestern)

///     Raihan Ruhin
///     CSE, Jahangirnagar University.
///     Dhaka-Bangladesh.
///     id: raihanruhin (topcoder / codeforces / codechef / uva / uvalive / spoj), 3235 (lightoj)
///     mail: raihanruhin@ (yahoo / gmail / facebook)
///     blog: ruhinraihan.blogspot.com

#include<bits/stdc++.h>
using namespace std;

#define SET(a) memset(a,-1,sizeof(a))
#define CLR(a) memset(a,0,sizeof(a))
#define PI acos(-1.0)

#define MOD 1000000007
#define MX 100000


int main()
{
    ios_base::sync_with_stdio(0);cin.tie(0);
    int tc, kk=1, nx,ny;
    double w, x;
    vector<double> d;
    while(cin>>nx>>ny>>w && nx)
    {
        bool flag=true;
        d.clear();
        d.push_back(-w/2.0);
        d.push_back(75.0 + w/2.0);
        for(int i=0;i<nx;i++)
        {
            cin>>x;
            d.push_back(x);
        }
        sort(d.begin(), d.end());
        for(int i=0;i<=nx;i++)
            if((d[i+1]-d[i])>w)
            {
                //cout<<d[i+1]<< " "<<d[i]<<endl;
                flag=false;
            }
        d.clear();
        d.push_back(-w/2.0);
        d.push_back(100.0 + w/2.0);
        for(int i=0;i<ny;i++)
        {
            cin>>x;
            d.push_back(x);
        }
        sort(d.begin(), d.end());
        for(int i=0;i<=ny;i++)
            if((d[i+1]-d[i])>w)
                flag=false;
        if(flag)    cout<<"YES\n";
        else cout<<"NO\n";
    }
return 0;
}

Word Index (UVA 417, UVALive 5392, ZOJ 1342, POJ 1496, HDU 1336, SCU 1024)

///     Raihan Ruhin
///     CSE, Jahangirnagar University.
///     Dhaka-Bangladesh.
///     id: raihanruhin (topcoder / codeforces / codechef / uva / uvalive / spoj), 3235 (lightoj)
///     mail: raihanruhin@ (yahoo / gmail / facebook)
///     blog: ruhinraihan.blogspot.com

#include<bits/stdc++.h>
using namespace std;

#define SET(a) memset(a,-1,sizeof(a))
#define CLR(a) memset(a,0,sizeof(a))
#define PI acos(-1.0)

#define MOD 1000000007
#define MX 100000

map<string, int> mp;
int cnt;

void precal(string s, int len)
{
    if(s.length()==len)
    {
        mp[s]=cnt++;
        return;
    }
    //cout<<s<<endl;
    char lst;
    if(s.length()==0)
        lst='a';
    else 
        lst = s[s.length()-1]+1;
    for(char ch=lst;ch<='z';ch++)
        precal(s+ch, len);
return;
}

int main()
{
    ios_base::sync_with_stdio(0);cin.tie(0);
    int tc, kk=1, n;
    string s;
    cnt=1;
    for(int i=1;i<=5;i++)
    {
        precal("", i);
       // cout<<i<<endl;
    }
    while(cin>>s)
    {
        cout<<mp[s]<<"\n";
    }

return 0;
}