Submission #1800881

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Source Code Expand

#include <bits/stdc++.h>

using namespace std;

#define REP(i, a, b) for (int i = (a), i##_end_ = (b); i < i##_end_; ++i)
#define debug(...) fprintf(stderr, __VA_ARGS__)
#define mp make_pair
#define x first
#define y second
#define pb push_back
#define SZ(x) (int((x).size()))
#define ALL(x) (x).begin(), (x).end()

template<typename T> inline bool chkmin(T &a, const T &b) { return b < a ? a = b, 1 : 0; }
template<typename T> inline bool chkmax(T &a, const T &b) { return a < b ? a = b, 1 : 0; }

typedef long long LL;

const int oo = 0x3f3f3f3f;

const int Mod = 1e9 + 7;

const int maxn = 110;

int n, step;
int a[maxn + 5];

int dp[maxn + 5][maxn + 5][maxn + 5];

int main()
{
#ifdef matthew99
	freopen("input.txt", "r", stdin);
	freopen("output.txt", "w", stdout);
#endif
	scanf("%d", &n), step = n, n = (n << 1) - 1;
	REP(i, 0, n) scanf("%d", a + i);
	sort(a, a + n);
	dp[0][1][0] = 1;
	int mid = n >> 1;
	REP(i, 0, step) 
	{
		if (i)
		{
			static int nxt[maxn + 5][maxn + 5];
			if (a[mid + i] != a[mid + i - 1])
			{
				memset(nxt, 0, sizeof nxt);
				REP(j, 1, n + 1) REP(k, 0, j)
					if (dp[i][j][k])
					{
						nxt[j + 1][k] = dp[i][j][k];
					}
				memcpy(dp[i], nxt, sizeof dp[i]);
			}
			if (a[mid - i] != a[mid - i + 1])
			{
				memset(nxt, 0, sizeof nxt);
				REP(j, 1, n + 1) REP(k, 0, j)
					if (dp[i][j][k])
					{
						nxt[j + 1][k + 1] = dp[i][j][k];
					}
				memcpy(dp[i], nxt, sizeof dp[i]);
			}
		}
		REP(j, 1, n + 1) REP(k, 0, j) if (dp[i][j][k]) REP(l, 0, j)
		{
			if (l < k)
			{
				(dp[i + 1][j - (k - l - 1)][l] += dp[i][j][k]) %= Mod;
			}
			else if (l == k)
			{
				(dp[i + 1][j][l] += dp[i][j][k]) %= Mod;
			}
			else if (l > k)
			{
				(dp[i + 1][j - (l - k - 1)][k + 1] += dp[i][j][k]) %= Mod;
			}
		}
	}
	int ans = 0;
	REP(i, 0, n + 1) REP(j, 0, i) (ans += dp[step][i][j]) %= Mod;
	(ans += Mod) %= Mod;
	printf("%d\n", ans);
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:36:45: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n), step = n, n = (n << 1) - 1;
                                             ^
./Main.cpp:37:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  REP(i, 0, n) scanf("%d", a + i);
                                 ^

Judge Result