Submission #47148

# Submission time Handle Problem Language Result Execution time Memory
47148 2018-04-28T07:31:20 Z PowerOfNinjaGo Boat (APIO16_boat) C++11
0 / 100
2000 ms 4744 KB
//Power Of Ninja Go
#include <bits/stdc++.h>
//#ifdef atom #else #endif
using namespace std;
typedef long long ll; typedef pair<int, int> ii; typedef vector<int> vi; typedef vector< ii > vii;
#define X first
#define Y second
#define pb push_back
const int maxn = 505;
const int md = 1e9+7;
void add(int &a, int b)
{
    a += b;
    if(a>= md) a-= md;
}
int mul(int a, int b)
{
    return (1LL*a*b)%md;
}
int expo(int a, int b)
{
    if(b == 0) return 1;
    int x = expo(a, b/2);
    int y = mul(x, x);
    if(b%2) y = mul(y, a);
    return y;
}
int inv(int x)
{
    return expo(x, md-2);
}
int a[maxn];
int b[maxn];
int qu[maxn][2*maxn];
int f[maxn][2*maxn];
int sum[maxn][2*maxn];
int n;
vi vec;
int g(int L, int R, int intv)
{
    //cout << L << ' ' << R << ' ' << intv << endl;
    int k = qu[R][intv]-qu[L-1][intv]-1;
    int sz = vec[intv+1]-vec[intv];
    int res = 1;
    //cout << sz << ' ' << k << endl;
    for(int i = sz; i<= sz+k; i++) res = mul(res, i);
    for(int i = 1; i<= k+1; i++) res = mul(res, inv(i));
    return res;
}
int main()
{
    cin >> n;
    for(int i = 1; i<= n; i++)
    {
        cin >> a[i] >> b[i];
        b[i]++;
        vec.pb(a[i]); vec.pb(b[i]);
    }
    sort(vec.begin(), vec.end()); vec.resize(unique(vec.begin(), vec.end())-vec.begin());
    for(int i = 1; i<= n; i++)
    {
        a[i] = lower_bound(vec.begin(), vec.end(), a[i])-vec.begin();
        b[i] = lower_bound(vec.begin(), vec.end(), b[i])-vec.begin();
    }
    for(int i = 1; i<= n; i++)
    {
        for(int j = 0; j< (int) vec.size()-1; j++)
        {
            qu[i][j] = qu[i-1][j] + (a[i]<= j && j< b[i]);
        }
    }
    for(int j = 0; j< (int) vec.size()-1; j++) sum[0][j] = 1;
    for(int i = 1; i<= n; i++)
    {
        for(int j = 0; j< (int) vec.size()-1; j++)
        {
            for(int a = 0; a< i; a++)
            {
                int sm;
                if(j == 0 && a == 0) sm = 1;
                else if(j == 0) sm = 0;
                else sm = sum[a][j-1];
                //cout << sm << endl;
                add(f[i][j], mul(sm, g(a+1, i, j)));
            }
            if(!(a[i]<= j && j <b[i])) f[i][j] = 0;
            //printf("f[%d][%d] = %d\n", i, j, f[i][j]);
            sum[i][j] = j?sum[i][j-1]:0;
            add(sum[i][j], f[i][j]);
        }
    }
    int res = 0;
    for(int i = 1; i<= n; i++)
    {
        for(int j = 0; j< (int) vec.size()-1; j++)
        {
            add(res, f[i][j]);
        }
    }
    cout << res << endl;
}
# Verdict Execution time Memory Grader output
1 Execution timed out 2069 ms 4744 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 2069 ms 4744 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 2059 ms 4744 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 2069 ms 4744 KB Time limit exceeded
2 Halted 0 ms 0 KB -