Codeforces Round #292 (Div. 2)

A. Drazil and Date

无算法，判断(s - (a + b)) % 2是否为零，若零，表示在s步内还能走向其他的地方并且回来
否则，都是No

#include <cstdio>

#include <iostream>

#include <cstring>

#include <cmath>

#include <algorithm>

#include <string>

#include <map>

#include <vector>

#include <set>

using namespace std;

const int MAXN = 1e6 + 10;

const int INF = 0x3f3f3f3f;

int main(void)

{

    //freopen ("A.in", "r", stdin);

    long long a, b, s;

    while (~scanf ("%I64d%I64d%I64d", &a, &b, &s))

    {

        if (a < 0)  a = -a;

        if (b < 0)  b = -b;

        if (a + b <= s)

        {

            int x = s - (a + b);

            if (x % 2 == 0) puts ("Yes");

            else    puts ("No");

        }

        else    puts ("No");

    }

    return 0;

}

B. Drazil and His Happy Friends

无算法，标记和更新happy的人就行了
少写一个&！，导致runtime error

#include <cstdio>

#include <iostream>

#include <cstring>

#include <cmath>

#include <algorithm>

#include <string>

#include <map>

#include <vector>

#include <set>

using namespace std;

const int MAXN = 1e6 + 10;

const int INF = 0x3f3f3f3f;

int a[110], b[110];

int main(void)

{

    //freopen ("B.in", "r", stdin);

    int n, m;

    scanf ("%d%d", &n, &m);

    memset (a, 0, sizeof (a));

    memset (b, 0, sizeof (b));

    int x, y, tmp, cnt = 0;

    scanf ("%d", &x);

    for (int i=0; i<x; ++i)

    {

        scanf ("%d", &tmp);

        a[tmp] = 1;

        cnt++;

    }

    scanf ("%d", &y);

    for (int i=0; i<y; ++i)

    {

        scanf ("%d", &tmp);

        b[tmp] = 1;

        cnt++;

    }

    for (int i=0; i<=m*n*2; ++i)

    {

        if (a[i%n] || b[i%m])

        {

            if (!a[i%n])    cnt++;

            if (!b[i%m])    cnt++;

            a[i%n] = b[i%m] = 1;

        }

    }

    (cnt == n + m) ? puts ("Yes") : puts ("No");

    return 0;

}

C. Drazil and Factorial

无算法，数学问题貌似就是对单个数字分解质因数，替换，然后sort排序就行了

#include <cstdio>

#include <iostream>

#include <cstring>

#include <cmath>

#include <algorithm>

#include <string>

#include <map>

#include <vector>

#include <set>

using namespace std;

const int MAXN = 1e6 + 10;

const int INF = 0x3f3f3f3f;

string res[10] = {"", "", "2", "3", "322", "5", "53", "7", "7222", "7332"};

int main(void)

{

    //freopen ("C.in", "r", stdin);

    int n;

    while (cin >> n)

    {

        string s, ans;

        cin >> s;

        for (int i=0; i<s.size(); ++i)

        {

            ans += res[s[i] - '0'];

        }

        sort (ans.begin (), ans.end ());

        reverse (ans.begin (), ans.end ());

        cout << ans << endl;

    }

    return 0;

}