Submission #253992

#	Time	Username	Problem	Language	Result	Execution time	Memory
253992		ne4eHbKa	Slon (COCI15_slon)	C++17	0 / 120	9 ms	1032 KiB

slon

//{ <defines>

#include <bits/stdc++.h>
using namespace std;

//#pragma comment(linker, "/stack:200000000")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
//#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math,-O3")

#define fr(i, n) for(int i = 0; i < n; ++i)
#define fo(n) fr(i, n)

#define re return
#define ef else if
#define ifn(x) if(!(x))
#define _  << ' ' <<

#define ft first
#define sd second
#define ve vector
#define pb push_back
#define eb emplace_back

#define sz(x) int((x).size())
#define bnd(x) x.begin(), x.end()
#define clr(x, y) memset((x), (y), sizeof (x))

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef ve<int> vi;

inline ll time() {re chrono :: system_clock().now().time_since_epoch().count();}
mt19937 rnd(time());
mt19937_64 RND(time());

template<typename t> inline void umin(t &a, t b) {a = min(a, b);}
template<typename t> inline void umax(t &a, t b) {a = max(a, b);}

int md = 998244353;

inline int m_add(int&a, int b) {a += b; if(a < 0) a += md; if(a >= md) a -= md; re a;}
inline int m_sum(int a, int b) {a += b; if(a < 0) a += md; if(a >= md) a -= md; re a;}
inline int m_mul(int&a, int b) {re a = 1ll * a * b % md;}
inline int m_prod(int a, int b) {re 1ll * a * b % md;}

int m_bpow(ll A, ll b) {
    int a = A % md;
    ll ans = 1;
    for(ll p = 1ll << 63 - __builtin_clzll(b); p; p >>= 1) {
        (ans *= ans) %= md;
        if(p & b)
            (ans *= a) %= md;
    }
    re ans;
}

//const ld pi = arg(complex<ld>(-1, 0));
//const ld pi2 = pi + pi;
const int oo = 2e9;
const ll OO = 4e18;
//} </defines>
const int N = 1e5 + 5;

struct f {
    int a, b;
    f operator* (const f t) const {
        re {
            (ll(a) * t.b + ll(b) * t.a) % md,
            ll(b) * t.b % md
        };
    }
    f operator+ (const f t) const {
        re {
            (a + t.a) % md,
            (b + t.b) % md
        };
    }
    void invert() {
        a = !a ? 0 : md - a;
        b = !b ? 0 : md - a;
    }
    void operator*= (const f t) {
        *this = *this * t;
    }
    void operator+= (const f t) {
        *this = *this + t;
    }
};

f eval(char *s, int &n) {
    if(*s == 'x') {n = 1; re {1, 0};}
    int z = 0;
    for(n = 0; s[n] >= '0' && s[n] <= '9'; ++n)
        ((z *= 10) += s[n] - '0') %= md;
    return {0, z};
}

f rec(char *s, int n, int *c) {
    ifn(n) re {0, 0};
    bool neg = false;
    bool mul = false;
    list<f> t;
    for(int i = 0; i < n; ) {
        int m;
        f z;
        if(s[i] == '(') {
            m = c[i] + 1;
            z = rec(s + i + 1, c[i] - 1, c + i + 1);
        } else {
            z = eval(s + i, m);
        }
        if(mul) {
            t.back() *= z;
            mul = false;
        } else {
            if(neg) {
                z.invert();
                neg = false;
            }
            t.push_back(z);
        }
        char op = s[i + m];
        if(op == '-') neg = true;
        if(op == '*') mul = true;
        i += m + 1;
    }
    f res{0, 0};
    for(const auto &i : t) res += i;
    re res;
}

void solve() {
    string s; cin >> s;
    int n = s.size();
    s += '#';
    int p;
    cin >> p >> md;
    stack<int> st;
    int c[n];
    for(int i = 0; i < n; ++i) {
        if(s[i] == '(') {
            st.push(i);
        }
        if(s[i] == ')') {
            c[st.top()] = i - st.top();
            st.pop();
        }
    }
    assert(st.empty());
    f a = rec(&s[0], n, c);
    for(int x = 0; x < md; ++x) {
        if((1ll * x * a.a + a.b) % md != p) continue;
        cout << x << endl;
        return;
    }
    cout << "wat\n";
    exit(5);
}

int main() {
#ifdef _LOCAL
    freopen("in.txt", "r", stdin);
    int tests; cin >> tests;
    for(int test = 1; test <= tests; ++test) {
		cerr << "case #" << test << endl;
        solve();
        cerr << endl;
    }
#else
//    freopen("input.txt", "r", stdin); freopen("output.txt", "w", stdout);
    ios_base :: sync_with_stdio(0); cin.tie(0); cout.tie(0);
    solve();
#endif
    return 0;
}

Compilation message (stderr)

slon.cpp: In function 'int m_bpow(ll, ll)':
slon.cpp:51:26: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
     for(ll p = 1ll << 63 - __builtin_clzll(b); p; p >>= 1) {
                       ~~~^~~~~~~~~~~~~~~~~~~~
slon.cpp: In member function 'f f::operator*(f) const':
slon.cpp:70:41: warning: narrowing conversion of '(((((ll)((int)((const f*)this)->f::a)) * ((ll)((int)t.f::b))) + (((ll)((int)((const f*)this)->f::b)) * ((ll)((int)t.f::a)))) % ((ll)md))' from 'll {aka long long int}' to 'int' inside { } [-Wnarrowing]
             (ll(a) * t.b + ll(b) * t.a) % md,
             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~
slon.cpp:71:25: warning: narrowing conversion of '((((ll)((int)((const f*)this)->f::b)) * ((ll)((int)t.f::b))) % ((ll)md))' from 'll {aka long long int}' to 'int' inside { } [-Wnarrowing]
             ll(b) * t.b % md
             ~~~~~~~~~~~~^~~~

• Subtask 1: 0 / 120