複数校9


Arithmetic Sequence
Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Total Submission(s): 0    Accepted Submission(s): 0
Problem Description
A sequence 
b1,b2,⋯,bn are called 
(d1,d2)-arithmetic sequence if and only if there exist 
i(1≤i≤n) such that for every 
j(1≤jj(i≤jTeacher Mai has a sequence 
a1,a2,⋯,an. He wants to know how many intervals 
[l,r](1≤l≤r≤n) there are that 
al,al+1,⋯,ar are 
(d1,d2)-arithmetic sequence.
 
Input
There are multiple test cases.
For each test case, the first line contains three numbers 
n,d1,d2(1≤n≤105,|d1|,|d2|≤1000), the next line contains 
n integers 
a1,a2,⋯,an(|ai|≤109).
 
Output
For each test case, print the answer.
 
Sample Input
 
   
5 2 -2 0 2 0 -2 0 5 2 3 2 3 3 3 3
 

Sample Output
 
   
12 5
 

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#include 
#include 
#include 

using namespace std;
#define N 100000 + 5
#define LL long long

int a[N];
int D1[N], D2[N];
int d1, d2;
int n;

int main()
{
    while(~scanf("%d%d%d", &n, &d1, &d2))
    {
        for(int i = 1; i <= n; i++)
        scanf("%d", a + i);

        D1[1] = D2[1] = 1;
        int cn1 = 1, cn2 = 1;
        for(int i = 2; i <= n; i++)
        {
            if(a[i] == a[i - 1] + d1)
            cn1++;
            else cn1 = 1;
            D1[i] = cn1;

            if(a[i] == a[i - 1] + d2)
            cn2++;
            else
            cn2= 1;
            D2[i] = cn2;
        }

//        for(int i = 1; i <= n; i++)
//        cout<= 2)
            {
                ans += D1[i];
            }
            else if(D2[i] >= 2)
            {
                int t = i - D2[i] + 1;
                ans += (D1[t] +  D2[i] - 1);
                //cout<

Too Simple
Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Total Submission(s): 429    Accepted Submission(s): 83
Problem Description
Rhason Cheung had a simple problem, and asked Teacher Mai for help. But Teacher Mai thought this problem was too simple, sometimes naive. So she ask you for help.
Teacher Mai has 
m functions 
f1,f2,⋯,fm:{1,2,⋯,n}→{1,2,⋯,n}(that means for all 
x∈{1,2,⋯,n},f(x)∈{1,2,⋯,n}). But Rhason only knows some of these functions, and others are unknown.
She wants to know how many different function series 
f1,f2,⋯,fm there are that for every 
i(1≤i≤n),
f1(f2(⋯fm(i)))=i. Two function series 
f1,f2,⋯,fm and 
g1,g2,⋯,gm are considered different if and only if there exist 
i(1≤i≤m),j(1≤j≤n),
fi(j)≠gi(j).
 
Input
For each test case, the first lines contains two numbers 
n,m(1≤n,m≤100).
The following are 
m lines. In 
i-th line, there is one number 
−1 or 
n space-separated numbers.
If there is only one number 
−1, the function 
fi is unknown. Otherwise the 
j-th number in the 
i-th line means 
fi(j).
 
Output
For each test case print the answer modulo 
109+7.
 
Sample Input
 
   
3 3 1 2 3 -1 3 2 1
 

Sample Output
 
   
1
Hint
The order in the function series is determined. What she can do is to assign the values to the unknown functions.
 

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#include 
#include 
#include 

using namespace std;
#define N 100 + 5
#define LL long long
const int mod = 1000000000 + 7;

int n, m;
int f[N][N];
int cnt;

int mul_pow(int a, int k)
{
    int res = 1;
    while(k)
    {
        if(k & 1)
        res = ((long long)res * a) % mod;
        a = ((long long)a * a) % mod;
        k >>= 1;
    }
    return res;
}

int fact(int a)
{
    int res = 1;
    for(int i = 1; i <= a; i++)
    res = ((LL)res * i) % mod;
    return res;
}

bool h[N];
int op[N];

int main()
{
    while(~scanf("%d%d", &n, &m))
    {
        memset(op, 0, sizeof op);
        int t;
        cnt = 0;
        for(int i = 1; i <= m; i++)
        {
            scanf("%d", &t);
            if(t == -1) {
                op[i] = 1;
                cnt++;
            }
            else
            {
                f[i][1] = t;
                for(int j = 2; j <= n; j++)
                scanf("%d", &f[i][j]);
            }
        }

        int flag = 0;

        for(int i = 1; i <= m; i++)
        {
            memset(h, false, sizeof h);
            if(op[i] == 0)
            for(int j = 1; j <= n; j++)
            {
                t = f[i][j];
                if(h[t] || t > n || t <= 0)
                {
                    //cout<= 1; j--)
                t = f[j][t];
                if(t != i)
                {
                    flag = 1;
                    break;
                }
            }
            if(flag) printf("0
"); else printf("1
"); } else { t = fact(n); int ans = mul_pow(t, cnt - 1); printf("%d
", ans); } } return 0; }