TIOJ 1032 . 土撥鼠 (Groundhog) ( Hash )

1032 - 土撥鼠 (Groundhog) | TIOJ INFOR Online Judge
對 ( a, b ) 加邊的時候，對 a 的 val 加上 ( a, b ) 的雜湊函數值，對 b 的 val 減下 ( a, b ) 的雜湊函數值
詢問的時候判斷是否對所有 u 的 val 相加總和為 0。

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

typedef long long ll;
typedef vector< int > vi;
typedef vector< vi > vvi;
typedef vector< ll > vl;
typedef vector< vl > vvl;
typedef pair< int, int > pii;
typedef vector< pii > vp;

int N, M;

void init(){
    cin >> N >> M;
}

const int MOD7122 = 1e9 + 9;

int BASE7122;

int hash7122( int x, int y ){
    return ( 1LL * x * BASE7122 + y ) % MOD7122;
}

void solve(){
    srand( time( NULL ) );
    BASE7122 = rand() % MOD7122;
    vi val7122( N );
    for( int i = 0; i < M; ++i ){
        int op; cin >> op;
        if( op == 0 ){
            int x, y; cin >> x >> y; if( not ( 0 <= x and x < N and 0 <= y and y < N ) ) continue;
            if( not ( x < y ) ) swap( x, y );
            ( val7122[ x ] += hash7122( x, y ) ) %= MOD7122;
            ( val7122[ y ] -= hash7122( x, y ) ) %= MOD7122;
        } else if( op == 1 ){
            int x, y; cin >> x >> y; if( not ( 0 <= x and x < N and 0 <= y and y < N ) ) continue;
            if( not ( x < y ) ) swap( x, y );
            ( val7122[ x ] -= hash7122( x, y ) ) %= MOD7122;
            ( val7122[ y ] += hash7122( x, y ) ) %= MOD7122;
        } else{
            int k; cin >> k;
            int sum = 0;
            for( int e = 0; e < k; ++e ){
                int u; cin >> u; if( not ( 0 <= u and u < N ) ) continue;
                ( sum += val7122[ u ] ) %= MOD7122;
            }
            cout << ( sum == 0 ) << endl;
        }
    }
}

signed main(){
    ios::sync_with_stdio( false );
    init();
    solve();
    return 0;
}