#include <bits/stdc++.h>
#include <unistd.h>
using namespace std;
#define REP(i,n) for(int _n=(n), i=0;i<_n;++i)
#define FOR(i,a,b) for(int i=(a),_b=(b);i<=_b;++i)
#define FORD(i,a,b) for(int i=(a),_b=(b);i>=_b;--i)
#define TRACE(x) cerr << "TRACE(" #x ")" << endl;
#define DEBUG(x) cerr << #x << " = " << (x) << endl;
typedef long long LL; typedef unsigned long long ULL;
#define BIGMOD 1000000007
#define MAX_N 10010
LL dp[MAX_N];
bool isValid(vector<int>& cukierki, int mask)
{
int sum = 0;
for (int i=0; i < cukierki.size(); i++)
{
if (!(mask & (1 << i))) continue;
if (cukierki[i] > sum + 1) return false;
sum += cukierki[i];
}
return true;
}
LL bruteSolve(vector<int> &cukierki)
{
sort(cukierki.begin(), cukierki.end());
LL res = 0;
for (int mask=1; mask < (1 << cukierki.size()); mask++)
{
res += isValid(cukierki, mask) ? 1 : 0;
}
return res;
}
LL solve(vector<int> &cukierki)
{
sort(cukierki.begin(), cukierki.end());
for (int i=0; i < MAX_N; i++) dp[i] = 0;
dp[0] = 1;
const int maxN = MAX_N - 1;
for (int v : cukierki)
{
for (int k=maxN; k >= v-1; --k)
{
LL ways = dp[k];
if (ways==0) continue;
//if (v > k + 1) continue; // => k < v - 1
int nv = min(maxN, k + v);
dp[nv] += ways;
if (dp[nv] > BIGMOD)
{
dp[nv] %= BIGMOD;
}
}
}
LL res = 0;
for (int i=1; i < MAX_N; i++)
{
//if (dp[i]) printf("%d: %lld\n", i, dp[i]);
res += dp[i];
}
return res % BIGMOD;
}
int main()
{
int n;
scanf("%d", &n);
vector<int> cukierki;
for (int i=0; i < n; i++)
{
int x;
scanf("%d", &x);
cukierki.emplace_back(x);
}
LL res = solve(cukierki);
printf("%lld\n", res);
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 | #include <bits/stdc++.h> #include <unistd.h> using namespace std; #define REP(i,n) for(int _n=(n), i=0;i<_n;++i) #define FOR(i,a,b) for(int i=(a),_b=(b);i<=_b;++i) #define FORD(i,a,b) for(int i=(a),_b=(b);i>=_b;--i) #define TRACE(x) cerr << "TRACE(" #x ")" << endl; #define DEBUG(x) cerr << #x << " = " << (x) << endl; typedef long long LL; typedef unsigned long long ULL; #define BIGMOD 1000000007 #define MAX_N 10010 LL dp[MAX_N]; bool isValid(vector<int>& cukierki, int mask) { int sum = 0; for (int i=0; i < cukierki.size(); i++) { if (!(mask & (1 << i))) continue; if (cukierki[i] > sum + 1) return false; sum += cukierki[i]; } return true; } LL bruteSolve(vector<int> &cukierki) { sort(cukierki.begin(), cukierki.end()); LL res = 0; for (int mask=1; mask < (1 << cukierki.size()); mask++) { res += isValid(cukierki, mask) ? 1 : 0; } return res; } LL solve(vector<int> &cukierki) { sort(cukierki.begin(), cukierki.end()); for (int i=0; i < MAX_N; i++) dp[i] = 0; dp[0] = 1; const int maxN = MAX_N - 1; for (int v : cukierki) { for (int k=maxN; k >= v-1; --k) { LL ways = dp[k]; if (ways==0) continue; //if (v > k + 1) continue; // => k < v - 1 int nv = min(maxN, k + v); dp[nv] += ways; if (dp[nv] > BIGMOD) { dp[nv] %= BIGMOD; } } } LL res = 0; for (int i=1; i < MAX_N; i++) { //if (dp[i]) printf("%d: %lld\n", i, dp[i]); res += dp[i]; } return res % BIGMOD; } int main() { int n; scanf("%d", &n); vector<int> cukierki; for (int i=0; i < n; i++) { int x; scanf("%d", &x); cukierki.emplace_back(x); } LL res = solve(cukierki); printf("%lld\n", res); return 0; } |
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