MnZn求助矩阵乘法WA#3
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MnZn求助矩阵乘法WA#3
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黑影洞人楼主2022/9/14 16:02
#include<cstdio>
#include<algorithm>
#include<cstring>
#define N 114
#define int long long
using namespace std;
int a[N],n,m;
struct matrix{
	int m[N][N];
	matrix(){memset(m,0,sizeof(m));}
	void set(){
		for(int i=1;i<=n;i++){
			for(int j=1;j<=n;j++){
				if(a[i]>a[j]){
					m[i][j]=-2147483647;
					continue;
				}
				m[i][j]=1;
				for(int k=1;k<j;k++){
					m[i][j]=max(m[i][j],m[i][k]+(a[k]<=a[i]));
				}
			}
		}
	}
	matrix operator*(const matrix &a)const{
		matrix ans;
		for(int k=1;k<=n;k++){
			for(int i=1;i<=n;i++){
				for(int j=1;j<=n;j++){
					ans.m[i][j]=max(ans.m[i][j],m[i][k]+a.m[k][j]);
				}
			}
		}
		return ans;
	}
	matrix operator^(int b){
		matrix res,a=*this;
		while(b){
			if(b&1)res=res*a;
			a=a*a;
			b>>=1;
		}
		return res;
	}
}b;
signed main(){
	scanf("%lld%lld",&n,&m);
	for(int i=1;i<=n;i++)scanf("%lld",&a[i]);
	b.set();
	b=b^m;
	int ans=1;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=n;j++){
			ans=max(ans,b.m[i][j]);
		}
	}	
	printf("%lld",ans);
	return 0;
}



2022/9/14 16:02
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