uvalive 10692 欧拉定理

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a^x=a^(x%phi(c)+phi(c)) (mod c)

a^phi(c)=1 (mod c)

#include<iostream>#include<cstdio>#include<cstring>using namespace std;//m^n%klong long eular(long long n){    long long ans=1,i;    for(i=2; i*i<=n; i++)    {        if(n%i==0)        {            ans*=i-1;            n/=i;            while(n%i==0)            {                ans*=i;                n/=i;            }        }    }    if(n>1)    {        ans*=n-1;    }    return ans;}long long quickpow(long long m,long long n,int k){    long long b = 1;    while (n > 0)    {        if (n & 1)            b = (b*m)%k;        n = n >> 1 ;        m = (m*m)%k;    }    return b%k;}long long m,a[110],x;int n;char s[100];long long e[110];int main(){    int ca=1;    while(scanf("%s",s))    {        if(s[0]=='#')break;        m=0;        int l=strlen(s);        for(int i=0; i<l; i++)        {            m=m*10+(s[i]-'0');        }        scanf("%d",&n);        for(int i=0; i<n; i++)scanf("%lld",&a[i]);        e[0]=eular(m);        for(int i=1;i<n;i++)e[i]=eular(e[i-1]);        long long b;        if(n!=1)        b=a[n-1]%e[n-2];        else b=a[n-1]%m;        for(int i=n-2; i>=0; i--)        {            if(i)            b=quickpow(a[i],b+e[i],e[i-1]);            else b=quickpow(a[i],b+e[i],m);        }        cout<<"Case #"<<ca++<<": ";        cout<<b<<endl;    }    return 0;}