P2613 【模板】有理数取余
1 #include <bits/stdc++.h> 2 using namespace std; 3 typedef long long ll; 4 const int p = 19260817; 5 inline ll read() { 6 ll res = 0; 7 char ch = getchar(); 8 while(!isdigit(ch) and ch != EOF) 9 ch = getchar(); 10 while(isdigit(ch)) { 11 res = (res << 3) + (res << 1) + (ch - '0'); 12 res %= p; 13 ch = getchar(); 14 } 15 return res; 16 } 17 void exgcd(ll a, ll b, ll &x, ll &y) { 18 if (b == 0) x = 1, y = 0; 19 else exgcd(b, a%b, y, x), y -= a/b * x; 20 } 21 int main() { 22 ll a = read(), b = read(); 23 if (b == 0) { 24 puts("Angry!"); 25 return 0; 26 } 27 ll x, y; 28 exgcd(b,p,x,y); 29 if (x < 0) x += p; 30 printf("%lld\n",x*a%p); 31 return 0; 32 }
