P2613 【模板】有理数取余 

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#include<cstdio>
#define re register
#define int long long
const int MOD = 19260817;

inline void read(int &a) {
    register char c;
    while (c = getchar(), c < '0' || c >'9');
    register int x(c - '0');
    while (c = getchar(), c >= '0' && c <= '9') {
        x = (x * 10 + c - '0') % MOD;
    }
    a = x;
}

int exgcd(int a, int b, int& x, int& y) {
    if (!b) {
        x = 1, y = 0;
        return a;
    }
    int d = exgcd(b, a % b, y, x);
    y -= a / b * x;
    return d;
}
int inv(int n, int mod) {
    int inv, k;
    exgcd(n, mod, inv, k);
    return (inv % mod + mod) % mod;
}

int frac(int a, int b, int mod) {
    return (a * inv(b, mod)) % mod;
}

int a, b;
signed main() {
    read(a), read(b);
    if (!(b % MOD)) {
        printf("Angry!\n");
        return 0;
    }
    printf("%lld\n", frac(a, b, MOD));
}