Submission #297036

#	Time	Username	Problem	Language	Result	Execution time	Memory
297036		arnold518	Skyscraper (JOI16_skyscraper)	C++14	20 / 100	975 ms	400560 KiB

skyscraper

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int MAXN = 14;
const ll MOD = 1e9+7;

int N, L, A[MAXN+10];
ll dp[(1<<MAXN)][MAXN][110];

ll solve(int mask, int bef, int sum)
{
	if(sum>L) return 0;
	if(mask==((1<<N)-1)) return 1;
	ll &ret=dp[mask][bef][sum];
	if(ret!=-1) return ret;

	ret=0;
	for(int i=0; i<N; i++)
	{
		if(mask&(1<<i)) continue;
		ret+=solve(mask|(1<<i), i, sum+abs(A[i]-A[bef]));
		ret%=MOD;
	}
	return ret;
}

int main()
{	
	scanf("%d%d", &N, &L);
	for(int i=0; i<N; i++) scanf("%d", &A[i]);

	memset(dp, -1, sizeof(dp));

	ll ans=0;
	for(int i=0; i<N; i++) ans=(ans+solve((1<<i), i, 0))%MOD;
	printf("%lld\n", ans);
}

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:33:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   33 |  scanf("%d%d", &N, &L);
      |  ~~~~~^~~~~~~~~~~~~~~~
skyscraper.cpp:34:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   34 |  for(int i=0; i<N; i++) scanf("%d", &A[i]);
      |                         ~~~~~^~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3: 0 / 80