求助！能过样例却爆零！

#include<iostream>
using namespace std;
int x(int a) {
    return (a>0?0:1);
}
int main()
{
    int n;
    cin>>n;
    bool flag=false;
    int a[100]{0},f=0,t=0,pointer=0,p=0;
    while (t<n*n) {
        cin>>a[pointer];
        t+=a[pointer++];
    }
    t=0;
    pointer=0;
    while (t<n*n) {
        for (int j=0;j<a[pointer];j++) {
            cout<<flag;
            p++;
            if (p==7) {
                cout<<endl;
                p=0;
            }
        }
        pointer++;
        t++;
        flag=x(flag);
    }
    return 0;
}