Submission #1244269

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Source Code Expand

#include <bits/stdc++.h>
#define MOD 1000000007
#define SIZE 123456
 
using namespace std;
typedef long long ll;

int N;
int A[SIZE],B[SIZE];
ll ans;

int main(){

cin>>N;
for(int i=0; i<N; i++) scanf("%d",&A[i]);

if(N%2==0){
    for(int i=0; i<N; i++){
        if(A[i]%2==0){
            cout<<0<<endl;
            return 0;
        }else{
            B[A[i]]++;
        }
    }
    for(int i=1; i<N; i++){
        if(i%2==1){
            if(B[i]!=2){
                cout<<0<<endl;
                return 0;
            }
        }
    }
    ans=1LL;
    for(int i=0; i<N/2; i++){
        ans=ans*2%MOD;
    }
    cout<<ans<<endl;
}else{
    for(int i=0; i<N; i++){
        if(A[i]%2==1){
            cout<<0<<endl;
            return 0;
        }else{
            B[A[i]]++;
        }
    }
    for(int i=0; i<N; i++){
        if(i%2==0){
            if(i==0){
                if(B[i]!=1){
                cout<<0<<endl;
                return 0;
                }
            }
            if(i!=0&&B[i]!=2){
                cout<<0<<endl;
                return 0;
            }
        }
    }
    ans=1LL;
    for(int i=0; i<N/2; i++){
        ans=ans*2%MOD;
    }
    cout<<ans<<endl;
}


return 0;
 
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:15:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
 for(int i=0; i<N; i++) scanf("%d",&A[i]);
                                         ^

Judge Result