#include <bits/stdc++.h> #ifdef LOC #include "debuglib.h" #else #define deb(...) #define DBP(...) #endif using namespace std; using ll = long long; using Vi = vector<int>; using Pii = pair<int, int>; #define pb push_back #define mp make_pair #define x first #define y second #define rep(i, b, e) for (int i = (b); i < (e); i++) #define each(a, x) for (auto& a : (x)) #define all(x) (x).begin(), (x).end() #define sz(x) int((x).size()) //#define MAX_TEST constexpr int MOD = 1e9+7; constexpr ll MOD_SQR = ll(MOD)*MOD; vector<ll> fact, factInv; int prefs[10005][10005]; ll modInv(ll a, ll m = MOD) { if (a == 1) return 1; return ((a - modInv(m%a, a))*m + 1) / a; } ll choose(ll n, ll k) { return fact[n] * factInv[k] % MOD * factInv[n-k] % MOD; } int main() { cin.sync_with_stdio(0); cin.tie(0); cout << fixed << setprecision(18); #ifdef MAX_TEST int n = 10000; int nSaved = 4800; int cnt[4] = {nSaved, n/2-nSaved, n/2-nSaved, nSaved}; int rad[3] = {1234, 234, 1987}; #else int n; cin >> n; string str[3]; int rad[3]; rep(i, 0, 3) { cin >> rad[i] >> str[i]; } int cnt[4] = {}; rep(i, 0, n) { int type = (str[1][i] == '1'); type |= (str[2][i] == '1') << 1; if (str[0][i] == '1') type ^= 3; cnt[type]++; } #endif fact.resize(n+5, 1); factInv.resize(n+5, 1); rep(i, 1, n+5) { fact[i] = fact[i-1] * i % MOD; factInv[i] = modInv(fact[i]); } rep(ones1, 0, cnt[0]+1) { rep(ones2, 0, cnt[3]+1) { int a = ones1+ones2; int b = ones1-ones2+cnt[3]; prefs[a][b] = int(choose(cnt[0], ones1) * choose(cnt[3], ones2) % MOD); } } int dim = cnt[0]+cnt[3]; for (int i = dim; i >= 0; i--) { for (int j = dim; j >= 0; j--) { int tmp = prefs[i][j] + prefs[i][j+1]; prefs[i][j] = (tmp >= MOD ? tmp-MOD : tmp); } } for (int i = dim; i >= 0; i--) { for (int j = dim; j >= 0; j--) { int tmp = prefs[i][j] + prefs[i+1][j]; prefs[i][j] = (tmp >= MOD ? tmp-MOD : tmp); } } ll ans = 1; rep(i, 0, n) ans = ans*2 % MOD; rep(ones1, 0, cnt[1]+1) { rep(ones2, 0, cnt[2]+1) { int a = ones1+ones2; int b = cnt[1]-ones1+ones2; int c = ones1+cnt[2]-ones2; int ra = rad[0]-a+1; int rb = max(rad[1]-b+1, rad[2]-c+1); ra = min(max(ra, 0), 10001); rb = min(max(rb, 0), 10001); ll opt1 = choose(cnt[1], ones1) * choose(cnt[2], ones2) % MOD; ll opt2 = prefs[ra][rb]; ans -= opt1*opt2; if (ans < 0) ans += MOD_SQR; } } ans %= MOD; if (ans < 0) ans += MOD; cout << ans << '\n'; return 0; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 | #include <bits/stdc++.h> #ifdef LOC #include "debuglib.h" #else #define deb(...) #define DBP(...) #endif using namespace std; using ll = long long; using Vi = vector<int>; using Pii = pair<int, int>; #define pb push_back #define mp make_pair #define x first #define y second #define rep(i, b, e) for (int i = (b); i < (e); i++) #define each(a, x) for (auto& a : (x)) #define all(x) (x).begin(), (x).end() #define sz(x) int((x).size()) //#define MAX_TEST constexpr int MOD = 1e9+7; constexpr ll MOD_SQR = ll(MOD)*MOD; vector<ll> fact, factInv; int prefs[10005][10005]; ll modInv(ll a, ll m = MOD) { if (a == 1) return 1; return ((a - modInv(m%a, a))*m + 1) / a; } ll choose(ll n, ll k) { return fact[n] * factInv[k] % MOD * factInv[n-k] % MOD; } int main() { cin.sync_with_stdio(0); cin.tie(0); cout << fixed << setprecision(18); #ifdef MAX_TEST int n = 10000; int nSaved = 4800; int cnt[4] = {nSaved, n/2-nSaved, n/2-nSaved, nSaved}; int rad[3] = {1234, 234, 1987}; #else int n; cin >> n; string str[3]; int rad[3]; rep(i, 0, 3) { cin >> rad[i] >> str[i]; } int cnt[4] = {}; rep(i, 0, n) { int type = (str[1][i] == '1'); type |= (str[2][i] == '1') << 1; if (str[0][i] == '1') type ^= 3; cnt[type]++; } #endif fact.resize(n+5, 1); factInv.resize(n+5, 1); rep(i, 1, n+5) { fact[i] = fact[i-1] * i % MOD; factInv[i] = modInv(fact[i]); } rep(ones1, 0, cnt[0]+1) { rep(ones2, 0, cnt[3]+1) { int a = ones1+ones2; int b = ones1-ones2+cnt[3]; prefs[a][b] = int(choose(cnt[0], ones1) * choose(cnt[3], ones2) % MOD); } } int dim = cnt[0]+cnt[3]; for (int i = dim; i >= 0; i--) { for (int j = dim; j >= 0; j--) { int tmp = prefs[i][j] + prefs[i][j+1]; prefs[i][j] = (tmp >= MOD ? tmp-MOD : tmp); } } for (int i = dim; i >= 0; i--) { for (int j = dim; j >= 0; j--) { int tmp = prefs[i][j] + prefs[i+1][j]; prefs[i][j] = (tmp >= MOD ? tmp-MOD : tmp); } } ll ans = 1; rep(i, 0, n) ans = ans*2 % MOD; rep(ones1, 0, cnt[1]+1) { rep(ones2, 0, cnt[2]+1) { int a = ones1+ones2; int b = cnt[1]-ones1+ones2; int c = ones1+cnt[2]-ones2; int ra = rad[0]-a+1; int rb = max(rad[1]-b+1, rad[2]-c+1); ra = min(max(ra, 0), 10001); rb = min(max(rb, 0), 10001); ll opt1 = choose(cnt[1], ones1) * choose(cnt[2], ones2) % MOD; ll opt2 = prefs[ra][rb]; ans -= opt1*opt2; if (ans < 0) ans += MOD_SQR; } } ans %= MOD; if (ans < 0) ans += MOD; cout << ans << '\n'; return 0; } |