ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#207309 | #2908. count | A_WTB_A | 100 | 1890ms | 79372kb | C++ | 638b | 2024-07-28 15:03:53 | 2024-07-28 15:03:55 |
answer
#include"bits/stdc++.h"
using namespace std;
typedef long long ll;
typedef pair<ll,ll>PLL;
const ll maxn=5e6+10,mod=1e9+7,inf=0x3f3f3f3f;
ll f[maxn],inv[maxn],n,m,t,ans;
ll c(ll n,ll m){
return f[n]*inv[m]%mod*inv[n-m]%mod;
}void init(){
inv[0]=inv[1]=f[0]=f[1]=1;
for(int i=2;i<=maxn-1;i++)f[i]=f[i-1]*i%mod,inv[i]=(mod-mod/i)*inv[mod%i]%mod;
for(int i=1;i<=maxn-1;i++)inv[i]=inv[i-1]*inv[i]%mod;
}
int main(){
ios::sync_with_stdio(false);
cin.tie(0),cout.tie(0);
cin>>t;
init();
while(t--){
cin>>n>>m;
cout<<(n*m-1)*c(n+m-2,n-1)%mod<<endl;
}
return 0;
}
Details
小提示:点击横条可展开更详细的信息
Test #1:
score: 20
Accepted
time: 290ms
memory: 79368kb
input:
10 1 1 2000 1997 117 1647 392 452 959 1883 1046 1627 1398 1124 1372 306 1799 1007 111 1765
output:
0 57631948 737963048 807538931 137760374 398194748 77480423 174938019 583393917 445670336
result:
ok 10 lines
Test #2:
score: 20
Accepted
time: 323ms
memory: 79368kb
input:
10 1 1 2000 1997 1218 1479 350 1244 784 1715 999 92 396 1393 1726 1511 624 756 900 317
output:
0 57631948 610566455 356523655 593949258 665757514 349394180 73375269 50652564 663822508
result:
ok 10 lines
Test #3:
score: 20
Accepted
time: 438ms
memory: 79372kb
input:
10 1 1 100000 99997 36934 50467 5497 37576 83775 15544 23817 68917 33052 49207 59924 39340 2708 2614...
output:
0 73866797 788834869 539491921 582239610 497376436 343937059 324406513 13225836 35059446
result:
ok 10 lines
Test #4:
score: 20
Accepted
time: 442ms
memory: 79368kb
input:
10 1 1 100000 99997 6792 14252 90281 65716 46434 67120 18977 30384 16191 33996 3425 10433 31783 4263...
output:
0 73866797 609230597 213203975 638117274 527713366 525065128 867713025 174019248 375031322
result:
ok 10 lines
Test #5:
score: 20
Accepted
time: 397ms
memory: 79372kb
input:
10 1 1 100000 99994 47270 99792 93093 92620 88764 20724 48143 99711 33293 89038 2816 16811 97638 670...
output:
0 796648553 5720713 279796657 802039459 22848874 23038351 610731858 629891152 812026839
result:
ok 10 lines