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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#291094#4104. 排列计数MoRanSky100 ✓144ms15644kbC++23857b2023-12-26 04:49:452023-12-26 04:49:46

Judging History

你现在查看的是最新测评结果

  • [2023-12-26 04:49:46]
  • 评测
  • 测评结果:100
  • 用时:144ms
  • 内存:15644kb
  • [2023-12-26 04:49:45]
  • 提交

answer

#include <cstdio>
#include <iostream>
using namespace std;
const int N = 1000001, P = 1e9 + 7;
typedef long long LL;
int n, m, fact[N], infact[N];
int f[N];
int power (int a, int b) {
	int res = 1;
	while (b) {
		if (b & 1) res = (LL)res * a % P;
		a = (LL)a * a % P;
		b >>= 1;
	}
	return res;
}
int C(int a, int b) {
	return (LL)fact[a] * infact[b] % P * infact[a - b] % P;
}
int main() {
	fact[0] = infact[0] = 1;
	for (int i = 1; i < N; i++) fact[i] = (LL)fact[i - 1] * i % P;
	infact[N - 1] = power(fact[N - 1], P - 2);
	for (int i = N - 2; i; i--) infact[i] = (LL)infact[i + 1] * (i + 1) % P;
	f[0] = f[2] = 1;
	for (int i = 3; i < N; i++) 
		f[i] = (LL)(i - 1) * (f[i - 1] + f[i - 2]) % P;
	int T; scanf("%d", &T);
	while (T--) {
		scanf("%d%d", &n, &m);
		printf("%d\n", (LL)C(n, m) * f[n - m] % P); 
	}
	return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 5
Accepted
time: 17ms
memory: 15644kb

input:

1000
1 1
7 0
2 2
5 1
2 1
3 0
2 1
1 1
3 0
1 0
6 2
4 1
4 0
2 0
6 2
5 1
5 0
5 2
3 1
4 0
7 0
2 1
4 0
1 0
2 1
2 1
1 1
5 1
4 2
3 0
3 2
7 1
7 0
8 0
1 0
7 1
2 2
6 2
3 1
6 1
5 0
7 0
2 0
3 2
1 0
2 2
5 1
6 2
5 1
7 0
4 1
7 1
2 1
7 0
8 1
7 0
6 1
1 0
7 2
5 0
3 1
5 2
4 0
2 2
1 1
4 0
4 2
5 2
6 1
5 0
1 0
6 2
4 2
8 0...

output:

1
1854
1
45
0
2
0
1
2
0
135
8
9
1
135
45
44
20
3
9
1854
0
9
0
0
0
1
45
6
2
0
1855
1854
14833
0
1855
1
135
3
264
44
1854
1
0
0
1
45
135
45
1854
8
1855
0
1854
14832
1854
264
0
924
44
3
20
9
1
1
9
6
20
264
44
0
135
6
14833
1
45
3
135
1854
0
1
135
1
1854
7420
7420
924
1
924
20
0
1
1855
3
7420
1
924
45
0...

result:

ok 1000 lines

Test #2:

score: 5
Accepted
time: 17ms
memory: 15640kb

input:

1000
1 0
1 1
3 3
2 0
8 8
7 3
1 1
8 1
7 2
7 6
3 0
5 5
6 6
2 0
1 1
8 5
6 4
7 7
4 0
1 0
6 6
6 5
3 2
1 0
6 1
8 4
7 3
6 5
7 5
4 4
7 5
2 0
8 5
2 2
3 0
5 4
1 1
3 2
3 0
6 1
3 3
6 5
8 4
5 5
4 2
3 1
1 1
2 0
7 7
3 1
6 5
6 5
1 0
5 1
8 4
8 6
4 4
1 0
6 3
8 1
7 6
7 6
8 1
7 3
3 0
8 2
7 5
4 4
6 4
3 1
2 0
7 7
2 2
8 3...

output:

0
1
1
1
1
315
1
14832
924
0
2
1
1
1
1
112
15
1
9
0
1
0
0
0
264
630
315
0
21
1
21
1
112
1
2
0
1
0
2
264
1
0
630
1
6
3
1
1
1
3
0
0
0
45
630
28
1
0
40
14832
0
0
14832
315
2
7420
21
1
15
3
1
1
1
2464
0
0
0
630
44
7420
9
1
10
1854
0
924
1
0
0
10
1
0
0
265
264
924
1
0
924
135
1
315
45
9
135
0
40
1
45
0
6
...

result:

ok 1000 lines

Test #3:

score: 5
Accepted
time: 16ms
memory: 15640kb

input:

1000
4 3
6 2
7 1
2 1
1 1
6 1
3 0
3 0
6 4
1 1
3 3
1 0
3 0
6 6
8 8
6 0
1 1
5 0
1 0
2 0
7 6
6 1
6 0
3 0
6 1
2 2
8 8
3 1
5 0
8 7
6 5
2 1
4 3
1 1
8 1
6 0
3 3
3 0
6 2
1 1
3 1
8 3
1 0
2 2
3 0
8 8
1 1
2 2
3 1
1 0
4 2
7 3
4 0
5 3
4 1
4 4
5 3
4 3
8 5
6 4
6 5
4 0
8 6
7 2
8 1
7 3
5 3
6 3
2 0
4 3
6 2
3 2
4 4
4 1...

output:

0
135
1855
0
1
264
2
2
15
1
1
0
2
1
1
265
1
44
0
1
0
264
265
2
264
1
1
3
44
0
0
0
0
1
14832
265
1
2
135
1
3
2464
0
1
2
1
1
1
3
0
6
315
9
10
8
1
10
0
112
15
0
9
28
924
14832
315
10
40
1
0
135
0
1
8
3
315
0
1
1
1
0
1
0
1
6
630
0
112
7420
1
6
44
0
8
315
1
7420
1
15
0
9
0
0
1
0
0
1
630
15
112
15
1
1
15
...

result:

ok 1000 lines

Test #4:

score: 5
Accepted
time: 16ms
memory: 15640kb

input:

1000
2 0
10 2
2 2
10 6
9 7
5 4
8 8
4 4
5 1
9 8
7 5
5 2
12 11
12 8
10 6
4 3
12 5
10 10
5 2
10 4
4 1
5 4
4 4
1 1
1 0
7 7
8 4
3 2
2 0
3 3
4 1
8 8
3 2
10 4
8 6
6 0
1 1
11 9
1 1
11 10
10 9
6 4
2 0
3 1
5 4
11 9
3 0
4 2
7 3
3 1
1 1
12 0
2 0
9 9
7 7
7 1
9 3
6 6
5 0
3 1
4 2
8 7
8 4
2 1
8 0
9 1
2 1
11 11
12 1...

output:

1
667485
1
1890
36
0
1
1
45
0
21
20
0
4455
1890
0
1468368
1
20
55650
8
0
1
1
0
1
630
0
1
1
8
1
0
55650
28
265
1
55
1
0
0
15
1
3
0
55
2
6
315
3
1
176214841
1
1
1
1855
22260
1
44
3
6
0
630
0
14833
133497
0
1
176214840
0
1890
2
14832
1
10
44
1
667485
1134
20
0
0
0
0
315
0
1
0
1
6
1
315
3
45
2
6
0
1
44
...

result:

ok 1000 lines

Test #5:

score: 5
Accepted
time: 8ms
memory: 15456kb

input:

1000
12 7
2 1
9 6
8 4
1 0
2 1
1 1
1 0
2 0
5 0
2 0
8 0
8 6
10 1
11 11
5 4
2 0
10 10
4 0
1 1
9 6
11 2
9 1
11 5
7 4
7 7
7 2
3 3
6 0
10 5
5 1
5 1
2 1
6 1
8 8
10 0
1 1
9 4
11 5
1 1
9 6
11 0
2 2
3 2
10 2
6 4
5 5
6 5
2 0
12 7
1 0
1 1
7 6
8 0
5 0
1 0
12 4
11 6
1 1
4 1
10 4
4 0
6 2
9 7
8 5
3 2
11 0
12 8
6 3
...

output:

34848
0
168
630
0
0
1
0
1
44
1
14833
28
1334960
1
0
1
1
9
1
168
7342280
133497
122430
70
1
924
1
265
11088
45
45
0
264
1
1334961
1
5544
122430
1
168
14684570
1
0
667485
15
1
0
1
34848
0
1
0
14833
44
0
7342335
20328
1
8
55650
9
135
36
112
0
14684570
4455
40
7342335
34848
40
176214840
2464
1334960
15
...

result:

ok 1000 lines

Test #6:

score: 5
Accepted
time: 16ms
memory: 15572kb

input:

1000
1 0
1 0
3 0
6 0
8 1
3 3
9 9
1 1
7 1
8 6
4 3
10 5
3 2
4 2
11 8
5 5
11 9
1 0
10 0
11 2
12 8
9 0
2 0
3 0
1 1
3 3
6 3
1 0
2 0
8 4
10 5
6 2
3 1
2 1
11 9
1 1
5 5
7 6
4 2
2 2
3 1
11 8
1 1
2 2
2 1
5 4
11 4
12 11
4 2
5 2
4 0
12 1
3 1
3 3
7 4
6 5
3 1
4 3
1 1
3 3
2 0
7 5
12 11
6 3
2 2
8 2
3 2
4 0
7 1
3 1
...

output:

0
0
2
265
14832
1
1
1
1855
28
0
11088
0
6
330
1
55
0
1334961
7342280
4455
133496
1
2
1
1
40
0
1
630
11088
135
3
0
55
1
1
0
6
1
3
330
1
1
0
0
611820
0
6
20
9
176214840
3
1
70
0
3
0
1
1
1
21
0
40
1
7420
0
9
1855
3
40
7420
0
1
1
0
34848
1
1
1334960
0
1
1854
36
0
0
21
0
20
244860
7342335
1
70
40
0
21
22...

result:

ok 1000 lines

Test #7:

score: 5
Accepted
time: 16ms
memory: 15636kb

input:

1000
29 25
47 32
76 8
99 12
78 26
40 15
60 54
92 9
16 16
15 5
9 5
60 15
78 63
24 6
50 24
29 7
88 56
64 32
4 1
53 47
51 35
14 14
98 86
11 7
26 3
86 86
80 7
87 81
25 10
52 32
30 28
58 51
21 6
1 0
1 0
91 66
48 22
1 1
40 4
27 26
57 24
10 1
3 2
8 2
81 52
42 9
31 21
72 43
86 28
24 0
91 62
27 21
71 44
37 4...

output:

213759
404403496
703037972
260916130
8049381
734267840
266922809
224688083
1
8887855
1134
847474204
615885227
426676945
354737956
185247475
989488344
730873071
8
83732158
373572160
1
17286870
2970
275294240
1
734817995
820064504
963233036
876400115
435
449755253
227057625
0
0
775215116
420332799
1
5...

result:

ok 1000 lines

Test #8:

score: 5
Accepted
time: 12ms
memory: 15528kb

input:

1000
36 26
8 7
88 38
64 26
39 35
11 6
23 22
83 62
51 7
96 85
66 12
92 15
15 13
8 7
33 27
16 9
40 22
65 48
9 6
34 9
69 33
62 6
93 22
30 11
34 13
52 52
33 5
29 19
99 97
97 10
73 58
81 62
49 42
28 15
50 19
21 3
87 35
85 31
99 11
90 43
1 0
57 54
13 2
30 11
24 6
75 28
99 17
88 40
11 0
39 17
37 9
37 36
18...

output:

537097313
0
621397312
30219349
740259
20328
0
118425551
428900821
750817393
199220141
238615422
105
0
293505520
21209760
292055390
18028066
168
156481384
824120310
357333025
20474909
751882367
143737826
1
325950354
281992437
4851
37563485
859517255
445824006
259681623
886407482
760549291
247299181
6...

result:

ok 1000 lines

Test #9:

score: 5
Accepted
time: 12ms
memory: 15608kb

input:

1000
42 21
69 20
32 13
88 29
40 20
98 52
17 0
45 43
90 30
85 39
66 44
32 28
4 3
3 3
91 81
18 0
67 53
51 1
57 44
90 75
70 4
17 15
19 8
52 25
57 51
97 5
13 8
9 6
25 18
44 34
68 20
20 0
48 23
21 8
47 45
85 24
85 38
21 21
38 24
89 32
21 17
35 23
66 4
23 14
86 46
75 45
14 4
55 32
63 17
13 1
90 12
50 10
1...

output:

78048433
514311354
883764768
867714930
845559995
314418696
91363714
990
62552207
414691550
292058342
323640
0
1
981537275
644546846
925175141
969323655
576832904
184008488
812849236
136
889161977
814069021
616386717
101777003
56628
168
891217800
6428991
615419275
927799753
815793173
450469609
1081
8...

result:

ok 1000 lines

Test #10:

score: 5
Accepted
time: 17ms
memory: 15640kb

input:

1000
180 180
573 558
367 150
254 239
580 383
844 95
790 658
390 245
796 724
661 175
409 249
451 316
541 109
593 193
616 368
711 704
485 112
991 534
908 895
97 46
806 283
583 252
164 21
914 324
144 51
434 219
113 56
569 299
849 208
583 162
394 296
150 86
547 299
110 17
895 195
761 23
701 211
424 78
4...

output:

1
999700925
608823314
895755333
500167130
424784199
640850472
880036566
409295595
803068101
897760950
960453132
917167739
836439476
656819252
317253366
724117800
971875168
77156714
235181479
199755274
339277428
683560698
615573972
710011182
942431814
125504760
413835096
497793974
18437071
84487551
7...

result:

ok 1000 lines

Test #11:

score: 5
Accepted
time: 16ms
memory: 15640kb

input:

1000
401 143
892 462
709 247
769 11
943 857
341 238
418 71
122 53
589 164
585 478
307 234
538 89
212 95
718 142
473 358
776 634
571 279
543 121
275 175
796 447
642 305
345 169
433 209
175 14
401 324
414 41
436 277
192 168
953 328
869 116
867 456
503 250
337 156
22 12
878 685
684 356
690 373
290 234
...

output:

735805484
876488170
656880547
780413176
878033995
775754310
993064177
303737301
979656073
753945341
204212750
23687095
631173379
311433737
13731742
930810550
273370059
194757709
334291601
822891532
721253156
459584016
793898970
64142809
788363814
653231858
76237204
24884186
528022834
130636949
61362...

result:

ok 1000 lines

Test #12:

score: 5
Accepted
time: 13ms
memory: 15596kb

input:

1000
186 49
742 283
150 144
190 83
286 183
537 456
297 182
162 116
274 162
991 393
449 148
371 42
247 194
727 465
181 72
363 110
188 63
937 468
589 247
914 171
617 22
230 43
89 56
655 629
751 41
749 704
218 77
42 25
932 537
742 87
751 541
131 29
203 193
210 204
960 816
227 138
921 465
455 213
630 21...

output:

920444202
199044648
705165609
141082647
806255914
731329451
841540048
848862331
374013922
503802974
661404887
559202139
708782996
602569528
528962496
625484524
14115792
463083667
262832123
828652400
44522792
646169668
378594657
282953717
10337621
324275056
515136915
501602172
535606852
357141852
596...

result:

ok 1000 lines

Test #13:

score: 5
Accepted
time: 84ms
memory: 15596kb

input:

500000
557 220
580 19
27 13
447 360
23 4
25 22
820 211
884 851
586 292
249 23
410 225
656 344
125 57
267 143
500 150
810 786
592 235
711 598
594 4
483 332
307 132
86 83
452 424
434 45
15 6
383 278
907 869
687 682
355 150
299 263
662 594
259 24
479 399
936 407
950 98
308 58
660 210
24 3
330 213
533 5...

output:

218990033
596599662
668114373
494984695
783337328
4600
418775848
498879222
767367101
437914601
72096482
206164805
350937855
562828041
72490284
803447927
747819358
263084546
127479963
141686953
459819010
204680
100443024
130550103
668147480
549129846
316682892
302952495
523592595
221187376
453798522
...

result:

ok 500000 lines

Test #14:

score: 5
Accepted
time: 76ms
memory: 15592kb

input:

500000
179 138
970 4
4 3
208 131
220 208
501 172
604 413
884 880
325 275
492 421
272 165
934 520
6 1
372 10
721 478
639 158
48 1
7 7
637 622
774 295
338 23
421 332
206 21
123 54
452 305
820 156
316 77
951 527
839 569
798 201
261 61
657 26
25 12
770 178
683 518
538 313
749 507
889 699
198 172
688 302...

output:

777368907
79546827
0
98404764
579270788
891514755
248106363
451458920
798114254
282205842
278208425
842136676
264
287943125
335174261
942103259
459215443
1
319374604
566471917
834185044
172107805
414939504
191846071
671630616
646045083
684968506
467735183
296369708
349094578
104059265
588415475
4008...

result:

ok 500000 lines

Test #15:

score: 5
Accepted
time: 139ms
memory: 15592kb

input:

500000
323382 286126
582651 493887
677066 227600
227845 205199
635909 229638
236822 171983
541112 145935
420255 206672
866356 816331
676947 105719
992971 206765
306336 144563
789900 142081
672826 432996
800074 493922
813264 533552
433620 268749
733907 649212
451261 194482
498613 465691
594196 502801...

output:

110437176
4951163
972861320
96779444
633400475
317851717
391304620
12499748
784937392
129447329
455957123
970125412
310217982
165600641
185931379
989305806
146407485
792718891
187841249
26483357
984782348
516867039
217882987
107154106
380327788
588777702
739936212
606102954
550966402
418764067
92149...

result:

ok 500000 lines

Test #16:

score: 5
Accepted
time: 139ms
memory: 15612kb

input:

500000
574428 178046
449385 184112
300899 175644
243886 15130
433377 302818
885834 41658
574760 25125
970543 44845
675847 420960
296205 242937
872721 400243
512534 370380
697302 194996
48635 9198
221606 111555
44332 18719
920788 607993
450331 155097
141872 1733
537336 235156
924555 573494
656053 429...

output:

544527194
470638914
154284564
70625842
177859636
587007219
812846404
234960984
695904736
3575271
578627344
552596099
101233874
452820298
310623275
565378870
879717122
440669610
114604483
986867620
204044945
965229198
719583449
341074692
940070976
844418500
643036634
217107346
356360921
156694100
579...

result:

ok 500000 lines

Test #17:

score: 5
Accepted
time: 125ms
memory: 15568kb

input:

500000
414742 305965
575019 61929
920977 55690
643179 524714
497618 177692
639378 210701
676972 494501
242771 46198
913263 821671
375132 95216
909739 423536
930976 578387
540531 248207
375760 131643
412439 14949
762141 53878
108840 69781
818807 690274
358520 103329
916559 387686
681110 438840
965527...

output:

876455198
260471707
764621865
7409021
559993630
681336885
140794445
800147566
764421198
270943548
87701072
808966712
712320367
91482903
336926999
673789528
157226406
196979939
357551398
595729805
143898681
164605945
896405675
729084018
44103036
614197617
261618555
65547348
285980537
797781551
789906...

result:

ok 500000 lines

Test #18:

score: 5
Accepted
time: 134ms
memory: 15456kb

input:

500000
622244 395
607873 135586
300306 64036
808828 657263
90199 73912
582767 104494
456452 198511
273098 271314
896106 804956
772159 261471
510554 88247
58367 22709
313701 146098
794234 686179
714716 662714
986593 274552
945169 443375
650087 188323
977427 236197
108346 97145
367285 26658
405774 217...

output:

724443109
375168938
268276635
158760821
747224299
364697313
623992202
920302125
964027368
450620422
860941412
672923871
9461784
827480381
25709732
738172268
916962714
230950784
127017621
389029893
665823331
771422765
749790292
109147949
595912977
323099100
686539903
832323190
971204821
873689363
403...

result:

ok 500000 lines

Test #19:

score: 5
Accepted
time: 138ms
memory: 15560kb

input:

500000
403974 292398
77227 1343
425895 355146
398753 220227
344368 23836
719455 102136
691184 488191
484438 378528
652473 300412
201270 20107
719516 192140
44209 8770
498219 297341
478199 338770
375093 29961
746938 242440
303501 294962
3690 1472
33667 16991
770489 51598
164199 155728
287640 10121
67...

output:

761625407
393047775
47002345
691701168
317256014
370100816
5256425
568980364
122494169
237698522
791573422
129337054
104632705
920923741
221941403
520403917
584062704
588104302
548767119
581227595
233220452
166182794
464140792
587191692
163940357
282815181
924001170
66931577
403217917
98201327
11811...

result:

ok 500000 lines

Test #20:

score: 5
Accepted
time: 144ms
memory: 15596kb

input:

500000
230525 61697
696936 258850
939217 837089
674458 99267
304476 290510
312419 159201
313456 22842
98741 14695
662492 147387
407553 195547
783155 100410
238903 90551
854340 793575
810888 330623
252130 177332
408806 287642
745885 367308
456706 378782
153478 112666
294221 86663
237678 150739
736054...

output:

284491620
225185755
126175631
375425138
142442279
770089453
378102232
925325764
151656134
482801529
884977766
925140210
692365592
358504613
80482650
297738157
66617146
151098743
441549615
964297450
643153674
300144815
920173950
106632025
164802245
891999763
274921024
142618290
348683013
489083674
18...

result:

ok 500000 lines