Codeforces #105 DIV2 ABCDE

开始按照顺序刷刷以前的CF。

#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <stack>
#include <queue>
#include <cctype>
#include <cstdio>
#include <string>
#include <vector>
#include <climits>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <algorithm>
#define LL long long
#define PI 3.1415926535897932626
using namespace std;
int gcd(int a, int b) {return a % b ==  ? b : gcd(b, a % b);}
int a[],d;
int main()
{
    while (cin>>a[]>>a[]>>a[]>>a[]>>d)
    {
        int ans = ;
        for (int i = ; i <= d; i++)
        {
            for (int j = ; j < ; j++)
                if (i % a[j] == )
            {
                ans ++;
                break;
            }
        }
        cout<<ans<<endl;
    }
    return ;
}

B贡献无数发WA。注意相遇的条件 直接double处理就可以。一直以为按照相应直接直接跳跃相应距离 直接int处理

#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <stack>
#include <queue>
#include <cctype>
#include <cstdio>
#include <string>
#include <vector>
#include <climits>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <algorithm>
#define LL long long
#define PI 3.1415926535897932626
using namespace std;
int gcd(int a, int b) {return a % b ==  ? b : gcd(b, a % b);}
int vp,vd,t,f,c;
int pos[];
int main()
{
    while (cin>>vp>>vd>>t>>f>>c)
    {
       if (vp >= vd) {puts("");continue;}
       int thev = vd - vp;
       double pospri = vp * t;int ans = ;
       while (pospri < c)
       {
           double ti = pospri / (double)thev;
           if ((double) vd * ti >= c) break;
           ans ++;
           pospri = pospri + f * vp +(double)  * ti * vp;
          // printf("%d\n",pospri);
           if (pospri >= c) break;
       }
       cout <<ans <<endl;
    }
    return ;
}

C 坑点比较多。注意b等于0的情况

#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <stack>
#include <queue>
#include <cctype>
#include <cstdio>
#include <string>
#include <vector>
#include <climits>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <algorithm>
#define LL long long
#define PI 3.1415926535897932626
using namespace std;
int gcd(int a, int b) {return a % b ==  ? b : gcd(b, a % b);}
int n,a,b;
int num[];
int main()
{
    while (cin >> n >> a >> b)
    {
        if (a > n || b > n){ puts("-1");continue;}
        if (a >  &&  b == )
        {
            if (n - a < ) {puts("-1");continue;}
            else
            {
                printf("1 1 ");
                for (int i =  ,k = ,j = ; j <= n && i <= a ; k++,i++) printf("%d ",k);
                for (int i = a + ; i <= n; i++) printf("%d ",a + );
                puts("");
            }
            continue;
        }
        for (int i = ; i < ; i++) num[i] = ;
        int cas = ;
        int sum = ;
        for (int i = ; i <= b + ; i++)
        {
            num[i] = sum + cas;
            sum += num[i];
        }
        cas = ;
        for (int i = b + ; i <= a + b + ;i ++)
        {
            num[i] = num[i - ] + cas;
        }
        for (int i = ; i <= n; i++)
            if (i == ) cout << num[i];
            else cout << ' ' << num[i];
        puts("");
    }
    return ;
}

D DP

#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <stack>
#include <queue>
#include <cctype>
#include <cstdio>
#include <string>
#include <vector>
#include <climits>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <algorithm>
#define LL long long
#define PI 3.1415926535897932626
using namespace std;
int gcd(int a, int b) {return a % b ==  ? b : gcd(b, a % b);}
int w,b;
double dp[][];
void init()
{
    for (int i = ; i < ; i++)
    {
        dp[i][] = 1.0;
        dp[][i] = 0.0;
    }
    for (int w = ; w < ; w++)
        for (int b = ; b < ; b++)
    {
        dp[w][b]  += 1.0 * w / (w + b);
        if (b >= )
            dp[w][b] += dp[w][b - ] * 1.0 * b / (w + b) * 1.0 * (b - ) / (w + b - ) * 1.0 * (b - ) / (w + b - );
        if (b >= )
            dp[w][b] += dp[w - ][b - ] * 1.0 * b / (w + b) * 1.0 * (b - ) / (w + b - ) * w / (w + b - );
    }
}
int main()
{
    init();
    while (scanf("%d%d",&w,&b) != EOF)
    printf("%.9lf\n",dp[w][b]);
    return ;
}

E DP预处理+DP

#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <stack>
#include <queue>
#include <cctype>
#include <cstdio>
#include <string>
#include <vector>
#include <climits>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <algorithm>
#define LL long long
#define PI 3.1415926535897932626
using namespace std;
int gcd(int a, int b) {return a % b ==  ? b : gcd(b, a % b);}
#define MAXN 110
#define MAXD 10010
int sum[MAXN][MAXD],dp[MAXN][MAXD],res[MAXN][MAXD];
int N,M;
int num[MAXN];
int main()
{
    while (scanf("%d%d",&N,&M) != EOF)
    {
        memset(dp,,sizeof(dp));
        memset(res,,sizeof(res));
        for (int i = ; i <= N; i++)
        {
            scanf("%d",&num[i]);
            sum[i][] = ;
            for (int j = ; j <= num[i];j++)
            {
                int tmp;
                scanf("%d",&tmp);
                sum[i][j] = sum[i][j - ] + tmp;
            }
            res[i][] = ;
            for (int j = ; j <= num[i]; j++)
              for (int k = ; k <= j; k++)
                res[i][j] = max(res[i][j],sum[i][k] + sum[i][num[i]] - sum[i][num[i] - (j - k)]);
        }
        for (int i = ; i <= N; i++)
            for (int j = ; j <= M; j++)
              for (int k = ; k <= num[i] && k <= j; k++)
              dp[i][j] = max(dp[i][j],max(dp[i - ][j],dp[i - ][j - k] + res[i][k]));
        printf("%d\n",dp[N][M]);
    }
    return ;
}