oj.uz

Submission #810437

# Submission time Handle Problem Language Result Execution time Memory
810437 2023-08-06T09:46:06 Z winter0101 Tents (JOI18_tents) C++14
100 / 100
 176 ms 147120 KB 
#include<bits/stdc++.h>
using namespace std;
#define all(fl) fl.begin(),fl.end()
#define pb push_back
#define fi first
#define se second
#define for1(i,j,k) for(int i=j;i<=k;i++)
#define for2(i,j,k) for(int i=j;i>=k;i--)
#define for3(i,j,k,l) for(int i=j;i<=k;i+=l)
#define lb lower_bound
#define ub upper_bound
#define sz(a) (int)a.size()
#define pii pair<int,int>
#define pli pair<long long,int>
#define gcd __gcd
#define lcm(x,y) x*y/__gcd(x,y)
#define pil pair<int,long long>
#define pll pair<long long,long long>
#define eb emplace_back
const long long du=1e9+7;
long long f[3001][3001];
long long combi[3001][3001];
long long pw[3001];
long long fact[6001];
long long inv[6001];
long long g[3001][3001];
long long pow(long long a, long long b, long long m) {
    a %= m;
    long long res = 1;
    while (b > 0) {
        if (b & 1)
            res = res * a % m;
        a = a * a % m;
        b >>= 1;
    }
    return res;
}
int m,n;
signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    //freopen("temp.INP","r",stdin);
    //freopen("temp.OUT","w",stdout);
    cin>>m>>n;
    pw[0]=1;
    for1(i,1,3000)pw[i]=(pw[i-1]*4)%du;
    fact[0]=1;
    for1(i,1,6000)fact[i]=(fact[i-1]*i)%du;
    for1(i,0,6000){
    inv[i]=pow(fact[i],du-2,du);
    }
    combi[0][0]=1;
    for1(i,1,3000){
    combi[i][0]=1;
    for1(j,1,3000){
    combi[i][j]=(combi[i-1][j-1]+combi[i-1][j])%du;
    }
    }
    f[0][0]=1;
    for1(i,0,m){
    for1(j,0,n){
    if (!f[i][j])continue;
    int t1=j*2+i,t2=i*2+j;
    if (t1>m||t2>n){
        f[i][j]=0;
        continue;
    }
    if (t1+1<=m&&t2+2<=n){
        long long dd=(combi[m-t1][1]*combi[n-t2][2])%du;
        f[i+1][j]=(f[i+1][j]+f[i][j]*dd)%du;
    }
    if (t1+2<=m&&t2+1<=n){
        long long dd=(combi[m-t1][2]*combi[n-t2][1])%du;
        f[i][j+1]=(f[i][j+1]+f[i][j]*dd)%du;
    }
    }
    }
    for1(i,0,m){
    for1(j,0,n){
    if (!f[i][j])continue;
    f[i][j]=(f[i][j]*inv[i+j])%du;
    }
    }
    long long ans=0;
    for1(i,0,m){
    for1(j,0,n){
    if (!f[i][j])continue;
    int t1=j*2+i,t2=i*2+j;
    int l1=m-t1,l2=n-t2;
    /*for1(k,min(l1,l2),min(l1,l2)){
        long long dd=(pw[k]*combi[l1][k])%du;
        dd=(dd*combi[l2][k])%du;
        dd=(dd*fact[k])%du;
        ans=(ans+f[i][j]*dd)%du;
    }*/
    g[t1][t2]=(g[t1][t2]+f[i][j])%du;
    }
    }
    for1(i,0,m){
    for1(j,0,n){
    if (!g[i][j])continue;
    if (i+1<=m){
        g[i+1][j]=(g[i+1][j]+g[i][j])%du;
    }
    if (i+1<=m&&j+1<=n){
        g[i+1][j+1]=(g[i+1][j+1]+g[i][j]*4*(n-j))%du;
    }
    }
    }
    for1(i,m,m){
    for1(j,0,n){
    ans=(ans+g[i][j])%du;
    }
    }
    cout<<(ans-1+du)%du;

}

Compilation message

tents.cpp: In function 'int main()':
tents.cpp:89:9: warning: unused variable 'l1' [-Wunused-variable]
   89 |     int l1=m-t1,l2=n-t2;
      |         ^~
tents.cpp:89:17: warning: unused variable 'l2' [-Wunused-variable]
   89 |     int l1=m-t1,l2=n-t2;
      |                 ^~

Subtask #1
48.0 / 48.0

# Verdict Execution time Memory Grader output
1 Correct 37 ms 70812 KB Output is correct
2 Correct 37 ms 70836 KB Output is correct
3 Correct 38 ms 71028 KB Output is correct
4 Correct 38 ms 71716 KB Output is correct
5 Correct 38 ms 71412 KB Output is correct
6 Correct 40 ms 72112 KB Output is correct
7 Correct 39 ms 71624 KB Output is correct
8 Correct 40 ms 72156 KB Output is correct
9 Correct 39 ms 71356 KB Output is correct
10 Correct 40 ms 72668 KB Output is correct
11 Correct 39 ms 70896 KB Output is correct
12 Correct 41 ms 73292 KB Output is correct

Subtask #2
52.0 / 52.0

# Verdict Execution time Memory Grader output
1 Correct 37 ms 70812 KB Output is correct
2 Correct 37 ms 70836 KB Output is correct
3 Correct 38 ms 71028 KB Output is correct
4 Correct 38 ms 71716 KB Output is correct
5 Correct 38 ms 71412 KB Output is correct
6 Correct 40 ms 72112 KB Output is correct
7 Correct 39 ms 71624 KB Output is correct
8 Correct 40 ms 72156 KB Output is correct
9 Correct 39 ms 71356 KB Output is correct
10 Correct 40 ms 72668 KB Output is correct
11 Correct 39 ms 70896 KB Output is correct
12 Correct 41 ms 73292 KB Output is correct
13 Correct 38 ms 70848 KB Output is correct
14 Correct 45 ms 80380 KB Output is correct
15 Correct 129 ms 128832 KB Output is correct
16 Correct 41 ms 73244 KB Output is correct
17 Correct 52 ms 81156 KB Output is correct
18 Correct 63 ms 88896 KB Output is correct
19 Correct 143 ms 136532 KB Output is correct
20 Correct 119 ms 123668 KB Output is correct
21 Correct 85 ms 104524 KB Output is correct
22 Correct 92 ms 108616 KB Output is correct
23 Correct 67 ms 99020 KB Output is correct
24 Correct 176 ms 147120 KB Output is correct
25 Correct 139 ms 133572 KB Output is correct
26 Correct 165 ms 140516 KB Output is correct
27 Correct 168 ms 144668 KB Output is correct