Submission #2288730

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Source Code Expand

#include <bits/stdc++.h>

#ifndef LOCAL
#define cerr dolor_sit_amet
#endif

#define mp make_pair
#define sz(x) ((int)((x).size()))
#define X first
#define Y second
#define all(x) (x).begin(), (x).end()

using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair < int , int > ipair;
typedef pair < ll , ll > lpair;
const int IINF = 0x3f3f3f3f;
const ll LINF = 0x3f3f3f3f3f3f3f3fll;
const double DINF = numeric_limits<double>::infinity();
const int MOD = 1000000007;
const double EPS = 1e-9;
const double PI = acos(-1.0);
const int DX[] = { 1,  0, -1,  0,  1, -1,  1, -1};
const int DY[] = { 0,  1,  0, -1,  1, -1, -1,  1};
ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
ll sqr(ll x) { return x*x; } ll sqr(int x) { return (ll)x*x; }
double sqr(double x) { return x*x; } ld sqr(ld x) { return x*x; }
mt19937 mmtw(960172);
ll rnd(ll x, ll y) { static uniform_int_distribution<ll> d; return d(mmtw) % (y - x + 1) + x; }

// ========================================================================= //

const int N = 300333;
char s[300333];

int main() {
    ios::sync_with_stdio(false);

    scanf("%s", s + 1);
    s[0] = '1';
    int n = strlen(s);
    s[n] = '1';
    ++n;

    static ll d[N][2][3];
    d[1][1][0] = 1;
    for (int i = 2; i <= n; ++i) {
        if (s[i-1] == '0' || s[i-1] == '?') {
            (d[i][0][0] = d[i-1][0][0] + d[i-1][1][0]) %= MOD;
            (d[i][0][1] = d[i-1][0][1] + d[i-1][1][1]) %= MOD;
            (d[i][0][2] = d[i-1][0][2] + d[i-1][1][2]) %= MOD;
        }
        if (s[i-1] == '1' || s[i-1] == '?') {
            if (i % 2 == 0) {
                (d[i][1][0] = d[i-1][0][0]) %= MOD;
                (d[i][1][1] = d[i-1][1][0] + d[i-1][1][1] + d[i-1][0][1]) %= MOD;
                (d[i][1][2] = d[i-1][1][2] + d[i-1][0][2]) %= MOD;
            } else {
                (d[i][1][0] = d[i-1][0][0] + d[i-1][1][0]) %= MOD;
                (d[i][1][1] = d[i-1][0][1]) %= MOD;
                (d[i][1][2] = d[i-1][0][2] + d[i-1][1][1] + d[i-1][1][2]) %= MOD;
            }
        }
    }
    cout << d[n][1][2] << "\n";

    return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:41:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%s", s + 1);
                       ^

Judge Result