#include <iostream>
#include <vector>
#include <algorithm>
#include <cassert>
#include <cmath>
#include <map>
using namespace std;
using ll = long long;
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
#define MAX(a, b) (((a) < (b)) ? (b) : (a))
int const nmax = 500;
int const modulo = 1000000007;
class ModuloRing{
private:
void gcd(int a, int b, int &x, int &y){
if(b == 0){
x = 1;
y = 0;
} else {
gcd(b, a % b, x, y);
int aux = x;
x = y;
y = aux - a / b * y;
}
}
public:
int number;
ModuloRing(ll number_ = 0){
number = number_ % modulo;
}
ModuloRing operator + (ModuloRing a) {
return {number + a.number};
}
ModuloRing operator - (ModuloRing a) {
return {modulo + number - a.number};
}
ModuloRing operator * (ModuloRing a) {
return {1LL * number * a.number};
}
ModuloRing operator / (ModuloRing a) {
int x, y;
gcd(a.number, modulo, x, y);
x %= modulo;
if(x < 0)
x += modulo;
return 1LL * number * x;
}
};
map<int,int> code;
vector<int> dist;
int a[1 + nmax], b[1 + nmax];
void normalize(int n){
vector<int> temp;
temp.push_back(0);
for(int i = 1; i <= n; i++){
temp.push_back(a[i]);
temp.push_back(b[i]);
}
sort(temp.begin(), temp.end());
temp.erase(unique(temp.begin(), temp.end()), temp.end());
dist = temp;
for(int i = 0; i < temp.size(); i++)
code[temp[i]] = i;
for(int i = 1;i <= n; i++){
a[i] = code[a[i]];
b[i] = code[b[i]];
}
}
ModuloRing choose[5 + 2 * nmax][1 + nmax];
ModuloRing dp[5 + nmax][5 + 2 * nmax];
ModuloRing fact[5 + nmax];
void computefact(){
fact[0] = 1;
for(int i = 1;i <= nmax; i++)
fact[i] = fact[i - 1] * i;
}
ModuloRing combfast[1 + nmax][1 + nmax];
void precompute(){
combfast[0][0] = 1;
for(int i = 1;i <= nmax; i++) {
combfast[i][0] = 1;
for(int j = 1; j <= i; j++)
combfast[i][j] = combfast[i - 1][j - 1] + combfast[i - 1][j];
}
}
ModuloRing comb(int n, int k){
if(n < k)
return 0;
if(n <= nmax)
return combfast[n][k];
ModuloRing result(1);
for(int i = n - k + 1; i <= n; i++)
result = result * i;
return result / fact[k];
}
int main()
{
int n;
cin >> n;
for(int i = 1;i <= n; i++) {
cin >> a[i] >> b[i];
b[i]++;
}
normalize(n);
computefact();
precompute();
for(int i = 1; i < dist.size() - 1; i++) {
int d = dist[i + 1] - dist[i];
for(int h = 1;h <= n; h++) {
ModuloRing snap = comb(d, h);
for(int j = h; j <= n; j++)
choose[i][j] = choose[i][j] + comb(j - 1, h - 1) * snap;
}
}
for(int i = 0; i < dist.size() - 1; i++)
dp[0][i] = 1;
for(int i = 1;i <= n; i++){
for(int j = a[i]; j < b[i]; j++){
int _count = 1;
for(int i2 = i - 1; 0 <= i2; i2--){
dp[i][j] = dp[i][j] + dp[i2][j - 1] * choose[j][_count];
if(a[i2] <= j && j < b[i2])
_count++;
}
}
for(int j = 1; j < dist.size() - 1; j++) {
dp[i][j] = dp[i][j] + dp[i][j - 1];
}
}
ModuloRing result(0);
for(int i = 1;i <= n; i++)
result = result + dp[i][dist.size() - 2];
cout << result.number;
return 0;
}
/*
2
1 10
5 20
*/
Compilation message
boat.cpp: In function 'void normalize(int)':
boat.cpp:69:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = 0; i < temp.size(); i++)
~~^~~~~~~~~~~~~
boat.cpp: In function 'int main()':
boat.cpp:123:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = 1; i < dist.size() - 1; i++) {
~~^~~~~~~~~~~~~~~~~
boat.cpp:133:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = 0; i < dist.size() - 1; i++)
~~^~~~~~~~~~~~~~~~~
boat.cpp:145:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j = 1; j < dist.size() - 1; j++) {
~~^~~~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
979 ms |
5476 KB |
Output is correct |
2 |
Correct |
965 ms |
5376 KB |
Output is correct |
3 |
Correct |
1008 ms |
5496 KB |
Output is correct |
4 |
Correct |
968 ms |
5376 KB |
Output is correct |
5 |
Correct |
981 ms |
5376 KB |
Output is correct |
6 |
Correct |
986 ms |
5376 KB |
Output is correct |
7 |
Correct |
972 ms |
5496 KB |
Output is correct |
8 |
Correct |
978 ms |
5376 KB |
Output is correct |
9 |
Correct |
969 ms |
5496 KB |
Output is correct |
10 |
Correct |
980 ms |
5376 KB |
Output is correct |
11 |
Correct |
961 ms |
5496 KB |
Output is correct |
12 |
Correct |
962 ms |
5376 KB |
Output is correct |
13 |
Correct |
964 ms |
5496 KB |
Output is correct |
14 |
Correct |
969 ms |
5496 KB |
Output is correct |
15 |
Correct |
972 ms |
5496 KB |
Output is correct |
16 |
Correct |
177 ms |
5368 KB |
Output is correct |
17 |
Correct |
192 ms |
5248 KB |
Output is correct |
18 |
Correct |
186 ms |
5344 KB |
Output is correct |
19 |
Correct |
190 ms |
5248 KB |
Output is correct |
20 |
Correct |
186 ms |
5248 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
979 ms |
5476 KB |
Output is correct |
2 |
Correct |
965 ms |
5376 KB |
Output is correct |
3 |
Correct |
1008 ms |
5496 KB |
Output is correct |
4 |
Correct |
968 ms |
5376 KB |
Output is correct |
5 |
Correct |
981 ms |
5376 KB |
Output is correct |
6 |
Correct |
986 ms |
5376 KB |
Output is correct |
7 |
Correct |
972 ms |
5496 KB |
Output is correct |
8 |
Correct |
978 ms |
5376 KB |
Output is correct |
9 |
Correct |
969 ms |
5496 KB |
Output is correct |
10 |
Correct |
980 ms |
5376 KB |
Output is correct |
11 |
Correct |
961 ms |
5496 KB |
Output is correct |
12 |
Correct |
962 ms |
5376 KB |
Output is correct |
13 |
Correct |
964 ms |
5496 KB |
Output is correct |
14 |
Correct |
969 ms |
5496 KB |
Output is correct |
15 |
Correct |
972 ms |
5496 KB |
Output is correct |
16 |
Correct |
177 ms |
5368 KB |
Output is correct |
17 |
Correct |
192 ms |
5248 KB |
Output is correct |
18 |
Correct |
186 ms |
5344 KB |
Output is correct |
19 |
Correct |
190 ms |
5248 KB |
Output is correct |
20 |
Correct |
186 ms |
5248 KB |
Output is correct |
21 |
Correct |
828 ms |
5376 KB |
Output is correct |
22 |
Correct |
827 ms |
5248 KB |
Output is correct |
23 |
Correct |
793 ms |
5368 KB |
Output is correct |
24 |
Correct |
813 ms |
5364 KB |
Output is correct |
25 |
Correct |
815 ms |
5368 KB |
Output is correct |
26 |
Correct |
919 ms |
5364 KB |
Output is correct |
27 |
Correct |
945 ms |
5368 KB |
Output is correct |
28 |
Correct |
934 ms |
5368 KB |
Output is correct |
29 |
Correct |
925 ms |
5368 KB |
Output is correct |
30 |
Correct |
915 ms |
5496 KB |
Output is correct |
31 |
Correct |
904 ms |
5380 KB |
Output is correct |
32 |
Correct |
916 ms |
5368 KB |
Output is correct |
33 |
Correct |
936 ms |
5372 KB |
Output is correct |
34 |
Correct |
907 ms |
5376 KB |
Output is correct |
35 |
Correct |
910 ms |
5408 KB |
Output is correct |
36 |
Correct |
965 ms |
5472 KB |
Output is correct |
37 |
Correct |
974 ms |
5472 KB |
Output is correct |
38 |
Correct |
936 ms |
5404 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
24 ms |
5248 KB |
Output is correct |
2 |
Correct |
24 ms |
5248 KB |
Output is correct |
3 |
Correct |
24 ms |
5248 KB |
Output is correct |
4 |
Correct |
24 ms |
5248 KB |
Output is correct |
5 |
Correct |
24 ms |
5248 KB |
Output is correct |
6 |
Correct |
24 ms |
5248 KB |
Output is correct |
7 |
Correct |
27 ms |
5248 KB |
Output is correct |
8 |
Correct |
25 ms |
5248 KB |
Output is correct |
9 |
Correct |
27 ms |
5248 KB |
Output is correct |
10 |
Correct |
25 ms |
5248 KB |
Output is correct |
11 |
Correct |
25 ms |
5248 KB |
Output is correct |
12 |
Correct |
24 ms |
5248 KB |
Output is correct |
13 |
Correct |
23 ms |
5248 KB |
Output is correct |
14 |
Correct |
24 ms |
5248 KB |
Output is correct |
15 |
Correct |
24 ms |
5248 KB |
Output is correct |
16 |
Correct |
17 ms |
5248 KB |
Output is correct |
17 |
Correct |
15 ms |
5248 KB |
Output is correct |
18 |
Correct |
16 ms |
5248 KB |
Output is correct |
19 |
Correct |
16 ms |
5248 KB |
Output is correct |
20 |
Correct |
16 ms |
5248 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
979 ms |
5476 KB |
Output is correct |
2 |
Correct |
965 ms |
5376 KB |
Output is correct |
3 |
Correct |
1008 ms |
5496 KB |
Output is correct |
4 |
Correct |
968 ms |
5376 KB |
Output is correct |
5 |
Correct |
981 ms |
5376 KB |
Output is correct |
6 |
Correct |
986 ms |
5376 KB |
Output is correct |
7 |
Correct |
972 ms |
5496 KB |
Output is correct |
8 |
Correct |
978 ms |
5376 KB |
Output is correct |
9 |
Correct |
969 ms |
5496 KB |
Output is correct |
10 |
Correct |
980 ms |
5376 KB |
Output is correct |
11 |
Correct |
961 ms |
5496 KB |
Output is correct |
12 |
Correct |
962 ms |
5376 KB |
Output is correct |
13 |
Correct |
964 ms |
5496 KB |
Output is correct |
14 |
Correct |
969 ms |
5496 KB |
Output is correct |
15 |
Correct |
972 ms |
5496 KB |
Output is correct |
16 |
Correct |
177 ms |
5368 KB |
Output is correct |
17 |
Correct |
192 ms |
5248 KB |
Output is correct |
18 |
Correct |
186 ms |
5344 KB |
Output is correct |
19 |
Correct |
190 ms |
5248 KB |
Output is correct |
20 |
Correct |
186 ms |
5248 KB |
Output is correct |
21 |
Correct |
828 ms |
5376 KB |
Output is correct |
22 |
Correct |
827 ms |
5248 KB |
Output is correct |
23 |
Correct |
793 ms |
5368 KB |
Output is correct |
24 |
Correct |
813 ms |
5364 KB |
Output is correct |
25 |
Correct |
815 ms |
5368 KB |
Output is correct |
26 |
Correct |
919 ms |
5364 KB |
Output is correct |
27 |
Correct |
945 ms |
5368 KB |
Output is correct |
28 |
Correct |
934 ms |
5368 KB |
Output is correct |
29 |
Correct |
925 ms |
5368 KB |
Output is correct |
30 |
Correct |
915 ms |
5496 KB |
Output is correct |
31 |
Correct |
904 ms |
5380 KB |
Output is correct |
32 |
Correct |
916 ms |
5368 KB |
Output is correct |
33 |
Correct |
936 ms |
5372 KB |
Output is correct |
34 |
Correct |
907 ms |
5376 KB |
Output is correct |
35 |
Correct |
910 ms |
5408 KB |
Output is correct |
36 |
Correct |
965 ms |
5472 KB |
Output is correct |
37 |
Correct |
974 ms |
5472 KB |
Output is correct |
38 |
Correct |
936 ms |
5404 KB |
Output is correct |
39 |
Correct |
24 ms |
5248 KB |
Output is correct |
40 |
Correct |
24 ms |
5248 KB |
Output is correct |
41 |
Correct |
24 ms |
5248 KB |
Output is correct |
42 |
Correct |
24 ms |
5248 KB |
Output is correct |
43 |
Correct |
24 ms |
5248 KB |
Output is correct |
44 |
Correct |
24 ms |
5248 KB |
Output is correct |
45 |
Correct |
27 ms |
5248 KB |
Output is correct |
46 |
Correct |
25 ms |
5248 KB |
Output is correct |
47 |
Correct |
27 ms |
5248 KB |
Output is correct |
48 |
Correct |
25 ms |
5248 KB |
Output is correct |
49 |
Correct |
25 ms |
5248 KB |
Output is correct |
50 |
Correct |
24 ms |
5248 KB |
Output is correct |
51 |
Correct |
23 ms |
5248 KB |
Output is correct |
52 |
Correct |
24 ms |
5248 KB |
Output is correct |
53 |
Correct |
24 ms |
5248 KB |
Output is correct |
54 |
Correct |
17 ms |
5248 KB |
Output is correct |
55 |
Correct |
15 ms |
5248 KB |
Output is correct |
56 |
Correct |
16 ms |
5248 KB |
Output is correct |
57 |
Correct |
16 ms |
5248 KB |
Output is correct |
58 |
Correct |
16 ms |
5248 KB |
Output is correct |
59 |
Correct |
1705 ms |
5472 KB |
Output is correct |
60 |
Correct |
1686 ms |
5496 KB |
Output is correct |
61 |
Correct |
1682 ms |
5376 KB |
Output is correct |
62 |
Correct |
1695 ms |
5404 KB |
Output is correct |
63 |
Correct |
1693 ms |
5496 KB |
Output is correct |
64 |
Correct |
1859 ms |
5376 KB |
Output is correct |
65 |
Correct |
1854 ms |
5496 KB |
Output is correct |
66 |
Correct |
1860 ms |
5376 KB |
Output is correct |
67 |
Correct |
1850 ms |
5496 KB |
Output is correct |
68 |
Correct |
1844 ms |
5376 KB |
Output is correct |
69 |
Correct |
1612 ms |
5380 KB |
Output is correct |
70 |
Correct |
1613 ms |
5376 KB |
Output is correct |
71 |
Correct |
1608 ms |
5496 KB |
Output is correct |
72 |
Correct |
1638 ms |
5376 KB |
Output is correct |
73 |
Correct |
1651 ms |
5376 KB |
Output is correct |
74 |
Correct |
253 ms |
5248 KB |
Output is correct |
75 |
Correct |
261 ms |
5368 KB |
Output is correct |
76 |
Correct |
256 ms |
5248 KB |
Output is correct |
77 |
Correct |
254 ms |
5248 KB |
Output is correct |
78 |
Correct |
265 ms |
5368 KB |
Output is correct |