素数判定(高速)
(give_us_tmp/is_prime.cpp)
Code
/**
* @brief 素数判定(高速)
*
* verified with :https://judge.yosupo.jp/problem/factorize
* submission :https://judge.yosupo.jp/submission/28308
*/
bool is_prime(ll n){
if(n<=1)return 0;
if(n==2)return 1;
if(n%2==0)return 0;
ll s=0,d=n-1;
while(d%2)d/=2,s++;
auto mod_pow=[](__int128_t a,__int128_t b,__int128_t n){
ll res=1;
while(b){
if(b%2)res=res*a%n;
a=a*a%n;
b/=2;
}
return (ll)(res);
};
for(ll e:{2,3,5,7,11,13,17,19,23,29,31,37}){
if(n<=e)break;
if(mod_pow(e,d,n)==1)continue;
bool b=1;
for(int i=0;i<s;i++){
if(mod_pow(e,d<<i,n)==n-1)b=0;
}
if(b)return 0;
}
return 1;
}
#line 1 "give_us_tmp/is_prime.cpp"
/**
* @brief 素数判定(高速)
*
* verified with :https://judge.yosupo.jp/problem/factorize
* submission :https://judge.yosupo.jp/submission/28308
*/
bool is_prime(ll n){
if(n<=1)return 0;
if(n==2)return 1;
if(n%2==0)return 0;
ll s=0,d=n-1;
while(d%2)d/=2,s++;
auto mod_pow=[](__int128_t a,__int128_t b,__int128_t n){
ll res=1;
while(b){
if(b%2)res=res*a%n;
a=a*a%n;
b/=2;
}
return (ll)(res);
};
for(ll e:{2,3,5,7,11,13,17,19,23,29,31,37}){
if(n<=e)break;
if(mod_pow(e,d,n)==1)continue;
bool b=1;
for(int i=0;i<s;i++){
if(mod_pow(e,d<<i,n)==n-1)b=0;
}
if(b)return 0;
}
return 1;
}
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