Submission #3285856
Source Code Expand
#include <bits/stdc++.h> #include <ext/pb_ds/assoc_container.hpp> #include <ext/pb_ds/tree_policy.hpp> using namespace std; using namespace __gnu_pbds; #define fi first #define se second #define mp make_pair #define pb push_back typedef long long ll; typedef pair<int,int> ii; typedef vector<int> vi; typedef long double ld; typedef tree<ii, null_type, less<ii>, rb_tree_tag, tree_order_statistics_node_update> pbds; vector<int> fact; vector<int> ifact; vector<int> inv; vector<int> pow2; const int MOD = (1e9 + 7); int add(int a, int b) { a+=b; while(a>=MOD) a-=MOD; return a; } int mult(int a, int b) { return (a*1LL*b)%MOD; } int modpow(int a, int b) { int r=1; while(b) { if(b&1) r=mult(r,a); a=mult(a,a); b>>=1; } return r; } int choose(int a, int b) { if(a<b) return 0; if(b==0) return 1; if(a==b) return 1; return mult(fact[a],mult(ifact[b],ifact[a-b])); } int inverse(int a) { return modpow(a,MOD-2); } void init(int _n) { fact.clear(); ifact.clear(); inv.clear(); pow2.clear(); fact.resize(_n+1); ifact.resize(_n+1); inv.resize(_n+1); pow2.resize(_n+1); pow2[0]=1; ifact[0]=1; fact[0]=1; for(int i=1;i<=_n;i++) { pow2[i]=add(pow2[i-1],pow2[i-1]); fact[i]=mult(fact[i-1],i); //ifact[i]=mult(ifact[i-1],inv[i]); } ifact[_n] = inverse(fact[_n]); for(int i=_n-1;i>=1;i--) { ifact[i] = mult(ifact[i + 1], i + 1); } for(int i=1;i<=_n;i++) { inv[i] = mult(fact[i-1],ifact[i]); } } int main() { ios_base::sync_with_stdio(0); cin.tie(0); init(5555); int n,a,b,c; cin>>n>>a>>b>>c; int res=0; for(int x=0;x<=n;x++) { for(int y=0;y<=n;y++) { int aleft = a - x; int bleft = b; int cleft = c - x - 3*y; if(aleft<0||bleft<0||cleft<0) continue; if(bleft%2!=0) continue; if(bleft==0&&cleft>0) continue; int ans = (bleft>0?choose(cleft+bleft/2 -1, cleft):1); ans = mult(ans, choose(bleft/2+aleft,aleft)); ans = mult(ans, choose(bleft/2+aleft+x,x)); ans = mult(ans, choose(bleft/2+aleft+x+y,y)); res=add(res,ans); } } cout<<res<<'\n'; }
Submission Info
Submission Time | |
---|---|
Task | J - 123 Pairs |
User | zscoder |
Language | C++14 (GCC 5.4.1) |
Score | 1500 |
Code Size | 2135 Byte |
Status | AC |
Exec Time | 54 ms |
Memory | 384 KB |
Judge Result
Set Name | Sample | All | ||||
---|---|---|---|---|---|---|
Score / Max Score | 0 / 0 | 1500 / 1500 | ||||
Status |
|
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Set Name | Test Cases |
---|---|
Sample | example0.txt, example1.txt |
All | 000.txt, 001.txt, 002.txt, 003.txt, 004.txt, 005.txt, 006.txt, 007.txt, 008.txt, 009.txt, 010.txt, 011.txt, 012.txt, 013.txt, 014.txt, 015.txt, 016.txt, 017.txt, 018.txt, 019.txt, 020.txt, 021.txt, 022.txt, 023.txt, 024.txt, 025.txt, 026.txt, 027.txt, 028.txt, 029.txt, 030.txt, 031.txt, 032.txt, 033.txt, 034.txt, 035.txt, 036.txt, 037.txt, 038.txt, 039.txt, 040.txt, 041.txt, 042.txt, 043.txt, 044.txt, 045.txt, 046.txt, 047.txt, 048.txt, 049.txt, example0.txt, example1.txt |
Case Name | Status | Exec Time | Memory |
---|---|---|---|
000.txt | AC | 36 ms | 384 KB |
001.txt | AC | 19 ms | 384 KB |
002.txt | AC | 19 ms | 384 KB |
003.txt | AC | 19 ms | 384 KB |
004.txt | AC | 19 ms | 384 KB |
005.txt | AC | 18 ms | 384 KB |
006.txt | AC | 19 ms | 384 KB |
007.txt | AC | 19 ms | 384 KB |
008.txt | AC | 18 ms | 384 KB |
009.txt | AC | 19 ms | 384 KB |
010.txt | AC | 18 ms | 384 KB |
011.txt | AC | 18 ms | 384 KB |
012.txt | AC | 19 ms | 384 KB |
013.txt | AC | 2 ms | 384 KB |
014.txt | AC | 2 ms | 384 KB |
015.txt | AC | 44 ms | 384 KB |
016.txt | AC | 5 ms | 384 KB |
017.txt | AC | 15 ms | 384 KB |
018.txt | AC | 4 ms | 384 KB |
019.txt | AC | 18 ms | 384 KB |
020.txt | AC | 13 ms | 384 KB |
021.txt | AC | 42 ms | 384 KB |
022.txt | AC | 17 ms | 384 KB |
023.txt | AC | 24 ms | 384 KB |
024.txt | AC | 43 ms | 384 KB |
025.txt | AC | 23 ms | 384 KB |
026.txt | AC | 33 ms | 384 KB |
027.txt | AC | 41 ms | 384 KB |
028.txt | AC | 27 ms | 384 KB |
029.txt | AC | 30 ms | 384 KB |
030.txt | AC | 41 ms | 384 KB |
031.txt | AC | 43 ms | 384 KB |
032.txt | AC | 21 ms | 384 KB |
033.txt | AC | 18 ms | 384 KB |
034.txt | AC | 19 ms | 384 KB |
035.txt | AC | 27 ms | 384 KB |
036.txt | AC | 11 ms | 384 KB |
037.txt | AC | 1 ms | 384 KB |
038.txt | AC | 54 ms | 384 KB |
039.txt | AC | 18 ms | 384 KB |
040.txt | AC | 18 ms | 384 KB |
041.txt | AC | 25 ms | 384 KB |
042.txt | AC | 19 ms | 384 KB |
043.txt | AC | 1 ms | 384 KB |
044.txt | AC | 1 ms | 384 KB |
045.txt | AC | 1 ms | 384 KB |
046.txt | AC | 1 ms | 384 KB |
047.txt | AC | 1 ms | 384 KB |
048.txt | AC | 1 ms | 384 KB |
049.txt | AC | 1 ms | 384 KB |
example0.txt | AC | 1 ms | 384 KB |
example1.txt | AC | 2 ms | 384 KB |