发个题目坑 二模03day1

#include "cstdio"
int a,b,n,i,p,f[60];
bool h[80];
int main(){
	freopen("seq2.in","r",stdin);
	freopen("seq2.out","w",stdout);
	scanf("%d%d%d",&a,&b,&n);
	a%=7;
	b%=7;
	f[1]=f[2]=1;
	h[9]=true;
	for(i=3;i<52;++i){
		f[i]=(a*f[i-1]+b*f[i-2])%7;
		if(n==i){
			printf("%d\n",f[i]);
			return 0;
		}
		if(h[f[i]*8+f[i-1]]){
			p=i-2;
			break;
		}else{
			h[f[i]*8+f[i-1]]=true;
		}
	}
	printf("%d\n", f[(n-1)%p+1]);
	return 0;
}

#include <cstdio>
int next[70000],to[70000],hl,head[3000],le[70000];
inline void addEdge(int f,int t,int v){
	++hl;
	next[hl]=head[f];
	to[hl]=t;
	le[hl]=v;
	head[f]=hl;
}
int i,j,k,l,a,b,c,m,n;
int qh,qt,q[600000],f[3000];
bool iq[3000],vis[3000];
void spfa(){
	vis[1]=iq[1]=true;
	qt=2;
	qh=1;
	q[1]=1;
	while(qh!=qt){
		i=q[qh];
		iq[i]=false;
		for(j=head[i];j!=0;j=next[j]){
			vis[k=to[j]]=true;
			l=le[j];
			if(f[i]+l>f[k]){
				f[k]=f[i]+l;
				if(!iq[i]){
					iq[i]=true;
					q[qt++]=k;
				}
			}
		}
		++qh;
	}
}
int main(int argc, char const *argv[]){
	freopen("path.in","r",stdin);
	freopen("path.out","w",stdout);
	scanf("%d%d",&n,&m);
	for(i=0;i<m;++i){
		scanf("%d%d%d",&a,&b,&c);
		addEdge(a,b,c);
	}
	spfa();
	if(!vis[n]){
		printf("-1\n");
	}else{
		printf("%d\n", f[n]);
	}
	return 0;
}