大意: 定义$f_1="c",f_2="ff",f_n=f_{n-2}+f_{n-1}$, 求所有"cff"的间距和.
记录c的个数, 总长度, 所有c到左边界距离和, 右边界距离和, 所有c的间距.
#include <iostream> #include <iostream> #include <algorithm> #include <cstdio> #include <math.h> #include <set> #include <map> #include <queue> #include <string> #include <string.h> #include <bitset> #define REP(i,a,n) for(int i=a;i<=n;++i) #define PER(i,a,n) for(int i=n;i>=a;--i) #define hr putchar(10) #define pb push_back #define lc (o<<1) #define rc (lc|1) #define mid ((l+r)>>1) #define ls lc,l,mid #define rs rc,mid+1,r #define x first #define y second #define io std::ios::sync_with_stdio(false) #define endl ' ' #define DB(a) ({REP(__i,1,n) cout<<a[__i]<<' ';hr;}) using namespace std; typedef long long ll; typedef pair<int,int> pii; const int P = 530600414, INF = 0x3f3f3f3f; ll gcd(ll a,ll b) {return b?gcd(b,a%b):a;} ll qpow(ll a,ll n) {ll r=1%P;for (a%=P;n;a=a*a%P,n>>=1)if(n&1)r=r*a%P;return r;} ll inv(ll x){return x<=1?1:inv(P%x)*(P-P/x)%P;} inline int rd() {int x=0;char p=getchar();while(p<'0'||p>'9')p=getchar();while(p>='0'&&p<='9')x=x*10+p-'0',p=getchar();return x;} //head const int N = 1e6+10; int n, m, a[N]; char s[N]; int ans[N], num[N], len[N], L[N], R[N]; void init(int n) { num[1]=1,len[1]=1,len[2]=2; REP(i,3,n) { len[i]=(len[i-2]+len[i-1])%P; num[i]=(num[i-2]+num[i-1])%P; L[i]=(L[i-2]+L[i-1]+(ll)num[i-1]*len[i-2]%P)%P; R[i]=((ll)num[i-2]*len[i-1]%P+R[i-1]+R[i-2])%P; ans[i]=(ans[i-2]+ans[i-1]+(ll)(num[i-2]+R[i-2])*num[i-1]%P+(ll)L[i-1]*num[i-2]%P)%P; } } int main() { init(203333); int t; scanf("%d", &t); REP(i,1,t) { scanf("%d", &n); printf("Case #%d: %d ", i,ans[n]); } }