A - K-City

Time limit : 2sec / Memory limit : 256MB

Score : 100 points

Problem Statement

In K-city, there are n streets running east-west, and m streets running north-south. Each street running east-west and each street running north-south cross each other. We will call the smallest area that is surrounded by four streets a block. How many blocks there are in K-city?

Constraints

2≤n,m≤100

Input

Input is given from Standard Input in the following format:

n m

Output

Print the number of blocks in K-city.

Sample Input 1

Copy

3 4

Sample Output 1

Copy

There are six blocks, as shown below:

Sample Input 2

Copy

2 2

Sample Output 2

Copy

There are one block, as shown below:

题目链接：http://abc069.contest.atcoder.jp/tasks/abc069_a

分析：结论就是ans=(a-1)*(b-1)

下面给出AC代码：

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 typedef long long ll;
 4 inline int read()
 5 {
 6     int x=0,f=1;
 7     char ch=getchar();
 8     while(ch<'0'||ch>'9')
 9     {
10         if(ch=='-')
11             f=-1;
12         ch=getchar();
13     }
14     while(ch>='0'&&ch<='9')
15     {
16         x=x*10+ch-'0';
17         ch=getchar();
18     }
19     return x*f;
20 }
21 inline void write(int x)
22 {
23     if(x<0)
24     {
25         putchar('-');
26         x=-x;
27     }
28     if(x>9)
29     {
30         write(x/10);
31     }
32     putchar(x%10+'0');
33 }
34 int main()
35 {
36     int a,b;
37     cin>>a>>b;
38     cout<<(a-1)*(b-1)<<endl;
39     return 0;
40 }

Return Top

B - i18n

Time limit : 2sec / Memory limit : 256MB

Score : 200 points

Problem Statement

The word internationalization is sometimes abbreviated to i18n. This comes from the fact that there are 18 letters between the first i and the last n.

You are given a string s of length at least 3 consisting of lowercase English letters. Abbreviate s in the same way.

Constraints

3≤|s|≤100 (|s| denotes the length of s.)
s consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:

Output

Print the abbreviation of s.

Sample Input 1

Copy

internationalization

Sample Output 1

Copy

i18n

Sample Input 2

Copy

smiles

Sample Output 2

Copy

s4s

Sample Input 3

Copy

xyz

Sample Output 3

Copy

x1z

题目链接：http://abc069.contest.atcoder.jp/tasks/abc069_b

分析：输出第一个，最后一个就好咯

下面给出AC代码：

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 typedef long long ll;
 4 inline int read()
 5 {
 6     int x=0,f=1;
 7     char ch=getchar();
 8     while(ch<'0'||ch>'9')
 9     {
10         if(ch=='-')
11             f=-1;
12         ch=getchar();
13     }
14     while(ch>='0'&&ch<='9')
15     {
16         x=x*10+ch-'0';
17         ch=getchar();
18     }
19     return x*f;
20 }
21 inline void write(int x)
22 {
23     if(x<0)
24     {
25         putchar('-');
26         x=-x;
27     }
28     if(x>9)
29     {
30         write(x/10);
31     }
32     putchar(x%10+'0');
33 }
34 char s[105];
35 int main()
36 {
37     cin>>s;
38     int len=strlen(s);
39     cout<<s[0]<<len-2<<s[len-1]<<endl;
40     return 0;
41 }

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C - 4-adjacent

Time limit : 2sec / Memory limit : 256MB

Score : 400 points

Problem Statement

We have a sequence of length N, a=(a₁,a₂,…,a_N). Each a_i is a positive integer.

Snuke's objective is to permute the element in a so that the following condition is satisfied:

For each 1≤i≤N−1, the product of a_i and a_i+1 is a multiple of 4.

Determine whether Snuke can achieve his objective.

Constraints

2≤N≤10⁵
a_i is an integer.
1≤a_i≤10⁹

Input

Input is given from Standard Input in the following format:

N
a₁ a₂ … a_N

Output

If Snuke can achieve his objective, print Yes; otherwise, print No.

Sample Input 1

Copy

3
1 10 100

Sample Output 1

Copy

Yes

One solution is (1,100,10).

Sample Input 2

Copy

4
1 2 3 4

Sample Output 2

Copy

No

It is impossible to permute a so that the condition is satisfied.

Sample Input 3

Copy

3
1 4 1

Sample Output 3

Copy

Yes

The condition is already satisfied initially.

Sample Input 4

Copy

2
1 1

Sample Output 4

Copy

No

Sample Input 5

Copy

6
2 7 1 8 2 8

Sample Output 5

Copy

Yes

题目链接：http://abc069.contest.atcoder.jp/tasks/arc080_a

分析：统计4的倍数，2的倍数还有不是这两个的倍数的数，然后2个2的倍数等于4的倍数，然后就这样了！

下面给出AC代码：

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 typedef long long ll;
 4 inline int read()
 5 {
 6     int x=0,f=1;
 7     char ch=getchar();
 8     while(ch<'0'||ch>'9')
 9     {
10         if(ch=='-')
11             f=-1;
12         ch=getchar();
13     }
14     while(ch>='0'&&ch<='9')
15     {
16         x=x*10+ch-'0';
17         ch=getchar();
18     }
19     return x*f;
20 }
21 inline void write(int x)
22 {
23     if(x<0)
24     {
25         putchar('-');
26         x=-x;
27     }
28     if(x>9)
29     {
30         write(x/10);
31     }
32     putchar(x%10+'0');
33 }
34 int main()
35 {
36     int n;
37     cin>>n;
38     int a=0,b=0,c=0;
39     for(int i=0;i<n;i++)
40     {
41         ll x;
42         x=read();
43         if(x%4==0)
44             a++;
45         else if(x%2==0)
46             b++;
47         else c++;
48     }
49     if(b>0)
50         c++;
51     if(a+1>=c)
52         cout<<"Yes"<<endl;
53     else 
54     cout<<"No"<<endl;
55     return 0;
56 }

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D - Grid Coloring

Time limit : 2sec / Memory limit : 256MB

Score : 400 points

Problem Statement

We have a grid with H rows and W columns of squares. Snuke is painting these squares in colors 1, 2, …, N. Here, the following conditions should be satisfied:

For each i (1≤i≤N), there are exactly a_i squares painted in Color i. Here, a₁+a₂+…+a_N=HW.
For each i (1≤i≤N), the squares painted in Color i are 4-connected. That is, every square painted in Color i can be reached from every square painted in Color i by repeatedly traveling to a horizontally or vertically adjacent square painted in Color i.

Find a way to paint the squares so that the conditions are satisfied. It can be shown that a solution always exists.

Constraints

1≤H,W≤100
1≤N≤HW
a_i≥1
a₁+a₂+…+a_N=HW

Input

Input is given from Standard Input in the following format:

H W
N
a₁ a₂ … a_N

Output

Print one way to paint the squares that satisfies the conditions. Output in the following format:

c₁₁ … c_1W
:
c_H1 … c_HW

Here, c_ij is the color of the square at the i-th row from the top and j-th column from the left.

Sample Input 1

Copy

2 2
3
2 1 1

Sample Output 1

Copy

1 1
2 3

Below is an example of an invalid solution:

1 2
3 1

This is because the squares painted in Color 1 are not 4-connected.

Sample Input 2

Copy

3 5
5
1 2 3 4 5

Sample Output 2

Copy

1 4 4 4 3
2 5 4 5 3
2 5 5 5 3

Sample Input 3

Copy

1 1
1
1

Sample Output 3

Copy

题目链接：http://abc069.contest.atcoder.jp/tasks/arc080_b

分析：从一个点可以到达其它所有的点，直接来一个水平填充好像就过了

下面给出AC代码：

 1 #include <bits/stdc++.h>
 2 using namespace std;
 3 typedef long long ll;
 4 inline int read()
 5 {
 6     int x=0,f=1;
 7     char ch=getchar();
 8     while(ch<'0'||ch>'9')
 9     {
10         if(ch=='-')
11             f=-1;
12         ch=getchar();
13     }
14     while(ch>='0'&&ch<='9')
15     {
16         x=x*10+ch-'0';
17         ch=getchar();
18     }
19     return x*f;
20 }
21 inline void write(int x)
22 {
23     if(x<0)
24     {
25         putchar('-');
26         x=-x;
27     }
28     if(x>9)
29     {
30         write(x/10);
31     }
32     putchar(x%10+'0');
33 }
34 int w,h,n;
35 int s[105][105];
36 int cnt[10005];
37 int main()
38 {
39     h=read();
40     w=read();
41     n=read();
42     for(int i=1;i<=n;i++)
43         cnt[i]=read();
44     int k=1;
45     for(int i=1;i<=h;i++)
46     {
47         if(i%2==1)
48         {
49             for(int j=1;j<=w;j++)
50             {
51                 if(cnt[k]==0)
52                 k++;
53                 cnt[k]--;
54                 s[i][j]=k;
55             }
56         }
57     else
58     {
59         for(int j=w;j>0;j--)
60         {
61             if(cnt[k]==0)
62               k++;
63             cnt[k]--;
64             s[i][j]=k;
65         }
66     }
67     }
68     for(int i=1;i<=h;i++)
69     {
70         for(int j=1;j<=w;j++)
71             printf("%d ",s[i][j]);
72         printf("\n");
73     }
74     return 0;
75 }