493B - Vasya and Wrestling (Codeforces)

#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
#include<algorithm>
#include<vector>
using namespace std;
#define pf printf
#define sf scanf
#define loop(i, n) for(i=0; i<(n); i++)
#define MAX 10000
typedef long long ll;
vector<int> a, b;

int main()
{
    ll n, m, sum1, sum2, i, sz, j;
    int last, cnt , ans ;
    while(cin >> n)
    {
        ans =0;
        cnt=0;
        sum1 = sum2 = 0;
        a.clear();
        b.clear();
        loop(j,n)
        {
            cin >> m;
            if(j==(n-1)) last = m;
            if(m>0)
            {
                a.push_back(m);
                sum1 +=m;
            }
            else
            {
                m *=(-1);
                b.push_back(m);
                sum2 += m;
            }
        }
        sz=0;
        //cout << sum1 << " " << sum2 << endl;
        if(sum1>sum2) ans = 1;
        else if(sum2>sum1) ans = 2;
        else
        {
            if(a.size()> b.size()) sz = b.size();
            else                   sz = a.size();
            loop(i, sz)
            {
                if(a[i]>b[i])
                {
                    ans = 1;;
                    cnt++;
                    break;
                }
                else if(a[i]<b[i])
                {
                    ans = 2;
                    cnt++;
                    break;
                }
            }
            if(cnt==0)
            {
                if(last>0) ans = 1;
                else       ans = 2;
            }
        }
        if(ans==1) cout << "first" << endl;
        else if(ans==2) cout << "second" << endl;
    }
    return 0;

}

496B - Secret Combination (Codeforces)

#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
#include<algorithm>
using namespace std;
#define pf printf
#define sf scanf
#define loop(i, n) for(i=0; i<(n); i++)
#define MAX 100

int n;
string s, s1,  minS;

bool min(string s1, string s2)
{
    int i;
    int check = false;
    loop(i, n)
    {
        if(s1[i]==s2[i]) continue;
        else if(s1[i]>s2[i])
        {
            check = true;
            break;
        }
        else
        {
            check = false;
            break;
        }
    }
    return check;
}
void addOne()
{
    int i;
    loop(i, n)
    {
        if(s1[i]=='9')
            s1[i] = '0';
        else
            s1[i]++;
    }
}
void rightShift()
{
    s = s.substr(n-1,1)+ s.substr(0,n-1);
}
int main()
{
    int i, j;
    cin >> n;
    cin >> s;
    minS = s;
    loop(i, n)
    {
       s1 = s;
       loop(j, 9)
       {
            addOne();
            if(min(minS, s1))
                minS = s1;
       }
       rightShift();
       if(min(minS, s))
            minS = s;
    }
    cout << minS << endl;
    return 0;
}

499B - Lecture (Codeforces)

#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
#include<algorithm>
#include<map>
using namespace std;
#define pf printf
#define sf scanf
#define loop(i, n) for(i=0; i<(n); i++)
#define MAX 100
map<string, string> mp;

int main()
{
    //freopen("in.txt","r",stdin);
    int n, m;
    string s1, s2;
    cin >> n >> m;
    while(m--)
    {
        cin >> s1 >> s2;
        if(s1.length()>s2.length())
            mp[s1] = s2;
        else
            mp[s1] = s1;
    }
    while(n--)
    {
        cin >> s1;
        cout << mp[s1] << " ";
    }
    cout << endl;
    return 0;
}

508B - Anton and currency you all know (Codeforces)

#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
#include<algorithm>
using namespace std;
#define pf printf
#define sf scanf
#define loop(i, n) for(i=0; i<(n); i++)
#define MAX 100

int main()
{
    string s;
    int i, len;
    int index, temp, odd;
    int flag=0;
    cin >> s;
    len = s.length();
    odd = s[len-1]-'0';
    for(i=len-1; i>=0; i--)
    {
        temp = s[i]-'0';
        if(temp%2==0)
        {
            flag++;
            if(flag==1)
            {
                index = i;
            }
            if(odd>temp)
            {
                index = i;
            }
        }
    }
    if(flag==0)
        cout <<"-1" << endl;
    else
    {
        swap(s[index], s[len-1]);
        cout << s << endl;
    }
    return 0;
}

465A - inc ARG

#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
#include<algorithm>
using namespace std;
#define ll long long
#define sf scanf
#define pf printf
#define loop(i, n) for(i=0; i<(n) ; i++)
#define MAX 100
int main()
{
    string s;
    int n, i;
    cin >> n;
    cin >> s;
    int c = 1;
    int count = 0;
    loop(i, n)
    {
        if(s[i]=='0' && c==1)
        {
            count++;
            c = 0;
        }
        else if(s[i]=='1' && c==1)
        {
            count++;
            c = 1;
        }
        else
            break;
    }
    cout << count << endl;
    return 0;
}

448A - Rewards (Codeforces)

#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
#include<algorithm>
using namespace std;
#define pf printf
#define sf scanf
#define loop(i, n) for(i=0; i<n; i++)
#define MAX 100

int main()
{
    int n;
    float a1, a2, a3, slv_a;
    float b1, b2, b3, slv_b;
    cin >> a1 >> a2 >> a3;
    cin >> b1 >> b2 >> b3;
    cin >> n;

    slv_a = ceil((a1+a2+a3)/5);
    slv_b = ceil((b1+b2+b3)/10);

    if((slv_a+slv_b)<=n)
        cout <<"YES" << endl;
    else
        cout << "NO" << endl;
    return 0;
}

450A - Jzzhu and Children (Codeforces)

#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
#include<algorithm>
using namespace std;
#define pf printf
#define sf scanf
#define loop(i, n) for(i=0; i<n; i++)
#define MAX 105
int a[MAX], index[MAX], step[MAX], step2[MAX], small[MAX];
float big[MAX];
int main()
{
    int n, m, ans, temp;
    int i, j, s=1, b=1, s2=1, sm=1;
    ans =0;
    temp =0;
    cin >> n >> m;
    i = 1;
    for(j=1; j<=n; j++)
    {
        cin >> a[j];
        small[sm++] = a[j];
        if(a[j]>m)
        {
            big[b] = a[j];
            index[i++] = j;
            step[s] = ceil(big[b]/m);
            step2[s2++] = step[s];
            b++;
            s++;
        }
    }
    if(b>1)
    {
        sort(step2, step2+s2);
        for(j=1; j<s; j++)
        {
            if(step2[s2-1]==step[j])
            {
                temp = j;
            }
        }
        ans = index[temp];
        cout << ans << endl;
    }
    else
    {
        i =1;
        for(j=1; j<=n ;j++)
        {
            if(small[sm-1]==a[j])
            {
                index[i++] = j;
            }
        }
        cout << index[i-1] << endl;
    }
    return 0;
}