NOI.AC
| ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
|---|---|---|---|---|---|---|---|---|---|
| #164558 | #2908. count | LZDQ | 100 | 16ms | 3636kb | C++ | 725b | 2022-11-04 12:06:57 | 2022-11-04 12:06:57 |
answer
#include<cstdio>
#include<algorithm>
#include<cstring>
typedef long long ll;
using namespace std;
const int MAXN=2e5+5,mod=1e9+7;
int n,m;
ll fac[MAXN],inv[MAXN];
ll Fstpw(ll a,int b){
ll res=1;
while(b){
if(b&1) res=res*a%mod;
b>>=1;
a=a*a%mod;
}
return res;
}
int main(){
//freopen("count.in","r",stdin);
//freopen("count.out","w",stdout);
n=2e5;
fac[0]=1;
for(int i=1; i<=n; i++)
fac[i]=fac[i-1]*i%mod;
inv[n]=Fstpw(fac[n],mod-2);
for(int i=n; i; i--)
inv[i-1]=inv[i]*i%mod;
int _; scanf("%d",&_);
while(_--){
scanf("%d%d",&n,&m);
printf("%lld\n",(1ll*n*m-1)%mod*fac[n+m-2]%mod*inv[n-1]%mod*inv[m-1]%mod);
}
//fclose(stdin);
//fclose(stdout);
return 0;
}
详细
小提示：点击横条可展开更详细的信息
Test #1:
score: 20
Accepted
time: 3ms
memory: 3636kb
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: 3ms
memory: 3636kb
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: 3ms
memory: 3632kb
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: 3ms
memory: 3636kb
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: 4ms
memory: 3632kb
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
