#include <cstdio>
#include <algorithm>
#include <vector>
using namespace std;
const int N = 10000;
const int NUMERIC = 2000000;
typedef long long ll;
const ll MM = 1000000007;
const int S = 1000000;
ll pw(ll a, ll b)
{
ll ans = 1, mul = a;
while( b > 0 ){
if( b%2 == 1) ans *= mul;
mul *= mul; b/=2;
ans %= MM; mul %= MM;
}
return ans;
}
ll div(ll a){ return pw(a, MM-2); }
struct data{
data(){}
data(int wi,int su,int ad,bool ch):wi(wi), su(su), ad(ad), ch(ch){}
int wi, su, ad;
bool ch; // T:a, F:b
bool operator<(const data &l) const{
if( wi != l.wi) return wi < l.wi;
return ch > l.ch;
}
};
int n;
ll a[N], b[N], d[NUMERIC];
vector<data> list[NUMERIC];
int main(void) {
scanf("%d", &n);
for (int i = 0; i < n; i++){
scanf("%lld %lld", &a[i], &b[i]);
a[i]--;
int val;
for(int j=2;j<=S;j++){
val = a[i] / j;
list[j].push_back(data(j, val, i, true) );
}
for(int j = val-1 ; j >= 0; j--){
int v = a[i] / (j+1) +1;
list[v].push_back(data(v, j, i, true) );
}
for(int j=2;j<=S;j++){
val = b[i] / j;
list[j].push_back(data(j, val, i, false) );
}
for(int j = val-1 ; j >= 0; j--){
int v = b[i] / (j+1) +1;
list[v].push_back(data(v, j, i, false) );
}
}
ll ans = 0, mul = 1, wi = 0;
for(int i=0;i<n;i++){
mul *= ll(b[i] - a[i]);
mul %= MM;
}
for(int i=2;i<=1000005;i++){
sort(list[i].begin(), list[i].end());
}
for(int i=2;i<=1000005;i++){
d[i-1] = mul;
int j;
for(j = 0; j < list[i].size(); j++){
int ad = list[i][j].ad;
if( list[i][j].ch ){ // a
mul *= div(b[ad] - a[ad]); mul%=MM;
a[ad] = list[i][j].su;
mul *= b[ad] - a[ad]; mul%=MM;
}
else{ // b
mul *= div(b[ad] - a[ad]); mul%=MM;
b[ad] = list[i][j].su;
mul *= b[ad] - a[ad]; mul%=MM;
}
}
wi = j;
}
for (int i = 1000005; i >= 1; i--) {
for (int j = i + i; j <= 1000005; j+=i) {
d[i] = (d[i] - d[j] + MM) % MM;
}
}
for (int i = 1; i <= 1000005; i++) {
ans += (ll) i * d[i];
ans = ans % MM;
}
printf("%lld\n", ans);
return 0;
}
/*
7
2 222222
20 222220
22 222202
200 222200
202 222022
220 222020
222 222002
*/
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1508 ms |
141880 KB |
Output is correct |
2 |
Correct |
1532 ms |
141880 KB |
Output is correct |
3 |
Correct |
1504 ms |
141880 KB |
Output is correct |
4 |
Correct |
2220 ms |
204448 KB |
Output is correct |
5 |
Correct |
2192 ms |
204448 KB |
Output is correct |
6 |
Correct |
2236 ms |
204448 KB |
Output is correct |
7 |
Correct |
2824 ms |
204448 KB |
Output is correct |
8 |
Correct |
2828 ms |
204448 KB |
Output is correct |
9 |
Correct |
2820 ms |
204448 KB |
Output is correct |
10 |
Correct |
2844 ms |
204448 KB |
Output is correct |
11 |
Memory limit exceeded |
492 ms |
262144 KB |
Memory limit exceeded |
12 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Halted |
0 ms |
0 KB |
- |