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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#579333#7900. Gifts from KnowledgeMaster640RE 22ms105952kbC++143.1kb2024-09-21 12:28:402024-09-21 12:28:42

Judging History

你现在查看的是最新测评结果

  • [2024-09-21 12:28:42]
  • 评测
  • 测评结果:RE
  • 用时:22ms
  • 内存:105952kb
  • [2024-09-21 12:28:40]
  • 提交

answer

//
// Created by 35263 on 2024/9/20.
//
//每次选择是否反转一行,每一行最多进行一次反转,只有转和不转两种情况
//观察到r*c这是一个矩阵
//感觉像是一个dp
//给定相同相反关系,求方案数的题目,那么就必然是建图解决
//决定做就去做
//二分图染色 3 - color[x]
//连线+二分图染色说明两个不能同时选
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxn = 1000005;
const ll mod = 1e9 + 7;
string str[maxn];
int n,m,cnt[maxn],vis[maxn*2];
vector<int>pos[maxn],g[maxn*2];
//有意识地去突破
//i代表第i行不反转,i+n代表第i行反转
//所以连接的话,如果1都在第j列,那么(i->i'+n,i'->i+n);
//如果两个1不在同一列,那么(i->i',i+n->i’+n);
//最后普dfs一遍计算连通块个数,ksm一下即可
ll ksm(int x,int b){
    ll ans=1;
    while(b){
        if(b&1)ans=(ans*x)%mod;
        b>>=1;
        x=(x*x)%mod;
    }
    return ans;
}
void update(){
   for(int i=1;i<=m;i++)pos[i].clear(),cnt[i]=0;
   for(int i=1;i<=2*n;i++)g[i].clear();
   for(int i=1;i<=2*n;i++)vis[i]=0;
}
void add(int x,int y){
    g[x].push_back(y);g[y].push_back(x);
}
int get_color(int x){
    for(auto v:g[x]){
        if(vis[v]) {
            if (vis[v] == vis[x])return false;
        }
        else {
            vis[v] = 3 - vis[x];
            get_color(v);
        }
    }
    return true;
}
void init(){
    cin>>n>>m;
    update();
    for(int i=1;i<=n;i++)cin>>str[i],str[i]=" "+str[i];
    for(int i=1;i<=m;i++){
        for(int j=1;j<=n;j++){
            if(str[j][i]=='1') {
                cnt[i] += (str[j][i] == '1');
                pos[i].push_back(j);
            }
        }
    }
    int flag=true;
    for(int i=1;i<=(m+1)/2;i++){
        if(i==m-i+1){
            if(cnt[i]>1){
                flag=false;
                break;
            }
            continue;
        }
        if(cnt[i]+cnt[m-i+1]>2){
            flag=false;
            break;
        }
    }
    if(!flag){
        cout<<0<<endl;
        return;
    }
    for(int i=1;i<=n;i++)add(i,i+n);
    for(int i=1;i<=(m+1)/2;i++){
        if(i==m-i+1)continue;
        if(pos[i].size()==2){
            int u=pos[i][0],v=pos[i][1];
            add(u,v);add(u+n,v+n);
        }
        else{
            if(pos[i].size()==1){
            int u=pos[i][0],v=pos[m-i+1][0];

                add(u,v+n);add(v,u+n);
            }
            else{
                int u=pos[m-i+1][0],v=pos[m-i+1][1];
                add(u,v);add(u+n,v+n);
            }
        }
    }
    int cnt_blocks=0;
    flag=true;
    for(int i=1;i<=2*n;i++){
        if(!vis[i]){
            vis[i]=1;
            if(get_color(i))cnt_blocks++;
            else flag=false;
        }
    }
   // cout<<cnt_blocks<<endl;
    if(flag)
    cout<<ksm(2,cnt_blocks)%mod<<endl;
    else
    cout<<0<<endl;
}
int main(){
    ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
    int t;
    cin>>t;
    while(t--){
        update();
        init();
    }
    return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 22ms
memory: 105952kb

input:

3
3 5
01100
10001
00010
2 1
1
1
2 3
001
001

output:

4
0
2

result:

ok 3 number(s): "4 0 2"

Test #2:

score: -100
Runtime Error

input:

15613
10 10
0000000000
0000000000
0000000000
0000000000
0000000000
0000000000
0000000000
0000000000
0000000000
0000000000
15 8
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
1 5
00000
5 9
000000000
000000000
0000...

output:


result: