逆元(费马小定理, 扩展欧几里得, 线性求逆元)

部分引自
博客1
博客2
博客3

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#include<iostream>
#include<cstring>
#include<cstdio>
#include<queue>
#include<cstdlib>
#include<cmath>
#include<stack>
#include<map>
#include<vector>
#include<algorithm>
using namespace std;
#define ll long long
#define lb long double
#define INF 0x3f3f3f3f
#define maxn 1000005
int x, y, n, p;
void exgcd(int a, int b){
    if(!b){x = 1; y = 0; return;}
    else exgcd(b, a % b);
    int t = x; x = y; y = t - a / b * y;
}
int main()
{
    scanf("%d %d", &n, &p);
    for(int i = 1 ; i <= n ; ++ i){
        exgcd(i, p);
        cout << (x + p) % p << endl;
    }
    return 0;
}

#include<iostream>
#include<cstring>
#include<cstdio>
#include<queue>
#include<cstdlib>
#include<cmath>
#include<stack>
#include<map>
#include<vector>
#include<algorithm>
using namespace std;
#define ll long long
#define lb long double
#define INF 0x3f3f3f3f
#define maxn 3000025
int x, y, n, p;
ll inv[maxn];
int main()
{
    scanf("%d %d", &n, &p);
    inv[1] = 1; inv[0] = 0;
    cout << "1" << endl;
    for(int i = 2 ; i <= n ; ++ i){
        inv[i] = (ll)(p - (p/i))*inv[p % i]%p;
        printf("%lld\n", inv[i]);
    }
    return 0;
}