Submission #59920407

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Source Code Expand

// #pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4.1,sse4.2,avx,avx2,popcnt,tune=native")
#include <bits/stdc++.h>
using namespace std;
#define REP_(I,N) for (int I=0,END=(N);I<END;I++)
#define rREP_(I,N) for (int I=(N)-1;I>=0;I--)
#define rep_(I,S,N) for (int I=(S),END=(N);I<END;I++)
#define rrep_(I,S,N) for (int I=(N)-1,START=(S);I>=START;I--)
#define FOR_(I,S,N) for (int I=(S),END=(N);I<=END;I++)
#define rFOR_(I,S,N) for (int I=(N),START=(S);I>=START;I--)

#define DEBUG
#ifdef DEBUG
#define debug(...) fprintf(stderr, __VA_ARGS__)
#define deputs(str) fprintf(stderr, "%s\n",str)
#else
#define debug(...)
#define deputs(str)
#endif // DEBUG
typedef unsigned long long ULL;
typedef unsigned long long ull;
typedef long long LL;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
const int INF=0x3f3f3f3f;
const LL INFF=0x3f3f3f3f3f3f3f3fll;
const LL maxn=2e6+7;
const double pi=acos(-1.0);
const double eps=1e-10;
template<typename T>inline void pr2(T x,int k=64) {REP_(i,k) printf("%d",(x>>i)&1); putchar(' ');}
template<typename T>inline void max_(T &A,T B) {(A<B) &&(A=B);}
template<typename T>inline void min_(T &A,T B) {(A>B) &&(A=B);}
inline ll fastgcd(ll a, ll b) {  // __gcd()
    if (!b) return a;
    ll az=__builtin_ctzll(a),bz=__builtin_ctzll(b),z=min(az,bz),diff; b>>=bz;
    while (a) {
        a>>=az, diff=b-a, az=__builtin_ctzll(diff);
        (b>a)&&(b=a), a=abs(diff);
    }
    return b<<z;
}
int startTime;
void startTimer() {startTime=clock();}
void printTimer() {debug("/--- Time: %ld milliseconds ---/\n",clock()-startTime);}
typedef array<int,5> ar5;
typedef array<int,4> ar4;
typedef array<int,3> ar3;
std::mt19937 rng(time(0));
std::mt19937_64 rng64(time(0));
vector<pii> direction4 = {{-1,0},{0,-1},{0,1},{1,0}};
vector<pii> direction8 = {{-1,-1},{-1,0},{1,1},{0,-1},{0,1},{1,-1},{1,0},{1,1}};

// const int mod = 1e9+7;
const int mod=998244353;
struct mint {
    long long x;
    mint():x(0) {}
    mint(long long x):x((x%mod+mod)%mod) {}
    // mint(long long x):x(x){}
    mint &fix() { x = (x%mod+mod)%mod; return *this; }
    mint operator-() const { return mint(0) - *this; }
    mint operator~() const { return mint(1) / *this; }
    mint &operator+=(const mint &a) { if ((x+=a.x)>=mod) x-=mod; return *this; }
    mint &operator-=(const mint &a) { if ((x+=mod-a.x)>=mod) x-=mod; return *this; }
    mint &operator*=(const mint &a) { (x*=a.x)%=mod; return *this; }
    mint &operator/=(const mint &a) { (x*=a.pow(mod-2).x)%=mod; return *this; }
    mint operator+(const mint &a)const { return mint(*this) += a; }
    mint operator-(const mint &a)const { return mint(*this) -= a; }
    mint operator*(const mint &a)const { return mint(*this) *= a; }
    mint operator/(const mint &a)const { return mint(*this) /= a; }
    mint pow(long long t) const {
        mint ret=1,cur=x;
        for (; t; t>>=1ll,cur=cur*cur)
            if (t&1) ret=ret*cur;
        return ret;
    }
    bool operator<(const mint &a)const { return x < a.x; }
    bool operator==(const mint &a)const { return x == a.x; }
};
istream & operator>>(istream &o,mint &a) { o>>a.x; a=a.fix(); return o; }
ostream & operator<<(ostream &o,const mint &a) { o<<a.x; return o; }

int B[maxn],MAX[2007][2007],MIN[2007][2007],CNT[2007][2007];
int solve() {
    int n,m;
    scanf("%d%d",&n,&m);
    FOR_(i,1,n) scanf("%d",&B[i]);
    int q=0;
    FOR_(i,1,n) if (B[i]==-1) q++;
    mint res=mint(m).pow(q);
    B[0]=m+1;
    FOR_(i,1,n-1) {
        int MIN=m+1,MAX=1,cl=0,cr=0;
        FOR_(j,1,i) if (B[j]!=-1) min_(MIN,B[j]); else cl++;
        FOR_(j,i+1,n) if (B[j]!=-1) max_(MAX,B[j]); else cr++;
        // printf("%d: %d->%d; cl,cr=%d,%d\n",i,MAX,MIN-1,cl,cr);
        // i和i+1不在同一个range当且仅当MIN-left>MAX-right
        FOR_(k,MAX,MIN-1) { // maxvalue-right = k
            mint rx;
            if (cr==0&&k==MAX) rx=1;
            else if (cr==0&&k!=MAX) continue;
            else {
                rx=mint(k).pow(cr);
                if (k!=MAX) rx-=mint(k-1).pow(cr);
            }
            mint lx=mint(m-k).pow(cl);
            // printf("%d %d: %lld * %lld\n",i,k,lx.x,rx.x);
            res+=lx*rx;
        }
    }
    printf("%lld\n",res.x);
    return 0;
}
int main() {
    // ios_base::sync_with_stdio(false);
    // cin.tie(0), cout.tie(0);
    int T = 1;
    // cin>>T;
    // scanf("%d",&T);
    startTimer();
    FOR_(_, 1, T) { solve(); }
    // printTimer();
}
/*
*/

Submission Info

Compile Error

Main.cpp: In function ‘int solve()’:
Main.cpp:87:10: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   87 |     scanf("%d%d",&n,&m);
      |     ~~~~~^~~~~~~~~~~~~~
Main.cpp:88:22: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   88 |     FOR_(i,1,n) scanf("%d",&B[i]);
      |                 ~~~~~^~~~~~~~~~~~

Judge Result