bzoj3884: 上帝與集合的正確用法 擴展歐拉定理
阿新 • • 發佈:2018-08-27
sse push link base linker als for 題意 com
題意:求\(2^{2^{2^{2^{...}}}}\%p\)
題解:可以發現用擴展歐拉定理不需要很多次就能使模數變成1,後面的就不用算了
\(a^b\%c=a^{b\%\phi c} gcd(b,c)==1\)
\(a^b\%c=a^{b\%\phi c+\phi c} gcd(b,c)!=1\)
//#pragma GCC optimize(2) //#pragma GCC optimize(3) //#pragma GCC optimize(4) //#pragma GCC optimize("unroll-loops") //#pragma comment(linker, "/stack:200000000") //#pragma GCC optimize("Ofast,no-stack-protector") //#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native") #include<bits/stdc++.h> #define fi first #define se second #define db double #define mp make_pair #define pb push_back #define pi acos(-1.0) #define ll long long #define vi vector<int> #define mod 998244353 #define ld long double #define C 0.5772156649 #define ls l,m,rt<<1 #define rs m+1,r,rt<<1|1 #define pll pair<ll,ll> #define pil pair<int,ll> #define pli pair<ll,int> #define pii pair<int,int> //#define cd complex<double> #define ull unsigned long long #define base 1000000000000000000 #define Max(a,b) ((a)>(b)?(a):(b)) #define Min(a,b) ((a)<(b)?(a):(b)) #define fin freopen("a.txt","r",stdin) #define fout freopen("a.txt","w",stdout) #define fio ios::sync_with_stdio(false);cin.tie(0) template<typename T> inline T const& MAX(T const &a,T const &b){return a>b?a:b;} template<typename T> inline T const& MIN(T const &a,T const &b){return a<b?a:b;} inline void add(ll &a,ll b){a+=b;if(a>=mod)a-=mod;} inline void sub(ll &a,ll b){a-=b;if(a<0)a+=mod;} inline ll gcd(ll a,ll b){return b?gcd(b,a%b):a;} inline ll qp(ll a,ll b){ll ans=1;while(b){if(b&1)ans=ans*a%mod;a=a*a%mod,b>>=1;}return ans;} inline ll qp(ll a,ll b,ll c){ll ans=1;while(b){if(b&1)ans=ans*a%c;a=a*a%c,b>>=1;}return ans;} using namespace std; const double eps=1e-8; const ll INF=0x3f3f3f3f3f3f3f3f; const int N=10000000+10,maxn=400000+10,inf=0x3f3f3f3f; int prime[N],cnt,phi[N]; bool mark[N]; void init() { phi[1]=1; for(int i=2;i<N;i++) { if(!mark[i]){prime[++cnt]=i;phi[i]=i-1;} for(int j=1;j<=cnt&&i*prime[j]<N;j++) { mark[i*prime[j]]=1; phi[i*prime[j]]=phi[i]*phi[prime[j]]; if(i%prime[j]==0) { phi[i*prime[j]]=phi[i]*prime[j]; break; } } } } int main() { init(); int T;scanf("%d",&T); while(T--) { vi v; ll p;scanf("%lld",&p); ll pp=p; while(p!=1) { v.pb(p); // printf("%lld\n",p); p=phi[p]; } ll now=1; for(int i=(int)v.size()-1;i>=0;i--) { now=qp(2,now,v[i])+(i?v[i]:0); } printf("%lld\n",now%pp); } return 0; } /******************** ********************/
bzoj3884: 上帝與集合的正確用法 擴展歐拉定理