#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> llp;
typedef pair<int, int> ii;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ii> vii;
typedef vector<vii> vvii;
#define pb(x) push_back(x)
#define mp(x, y) make_pair(x, y)
#define MOD ((ll)1e9+7)
#define safeadd(x, y) ( ( ((ll)x % MOD) + ((ll)y % MOD) ) % MOD )
int N;
map<int, ll> dp[500];
int A[500], B[500];
ll func(int x, int s) {
s = max(s, A[x]-1);
s = min(s, B[x]);
//cerr << "called: " << x << " " << s << endl;
if (dp[x][s] != -1) return dp[x][s];
ll sum = 0;
if (x < N-1) sum = safeadd(sum, func(x+1, 0));
else sum = safeadd(sum, 1);
for (int i = s+1; i <= B[x]; i++) {
if (x < N-1) sum = safeadd(sum, func(x+1, i));
else sum = safeadd(sum, 1);
}
dp[x][s] = sum;
//cerr << "returned: " << sum << endl;
return dp[x][s];
}
int main(int argc, char **argv) {
//freopen("input", "r", stdin);
//freopen("output", "w", stdout);
scanf("%d", &N);
for (int i = 0; i < N; i++) {
scanf("%d%d", &(A[i]), &(B[i]));
}
for (int i = 0; i < N; i++) {
dp[i][0] = -1;
for (int j = A[i]-1; j <= B[i]; j++) {
dp[i][j] = -1;
}
}
printf("%lld\n", safeadd(func(0, 0), -1));
return 0;
}
Compilation message
boat.cpp: In function 'int main(int, char**)':
boat.cpp:41:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d", &N);
^
boat.cpp:43:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d", &(A[i]), &(B[i]));
^
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
0 ms |
2184 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
0 ms |
2184 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
2000 ms |
361884 KB |
Execution timed out |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
0 ms |
2184 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |