spell bob august challenge..whats wrong in my code....the error being shown is run time eror

#include<iostream>

using namespace std; int check(char exp1[],char expp2[]); int main() { int t; cin>>t;

int k=0;
    int a[k]={0};

while(t-->0)
{

    char exp1[3],expp2[3];
    cin>>exp1;
    cin>>expp2;
    int countb=0,counto=0,i,j;
    int f=check(exp1,expp2);
    for(i=0;i<3;i++)
    {
        if(exp1[i]=='b')
        countb++;
        else if(exp1[i]=='o')
        counto++;
        else
        continue;
    }

    for(i=0;i<3;i++)
    {
        if(expp2[i]=='b')
        countb++;
        else if(expp2[i]=='o')
        counto++;
        else
        continue;
    }

    if(f==1&&countb>=2&&counto>=1)
    a[k++]=1;
    else
    a[k++]=0;
//  cout<<"t="<<t<<endl;

}
for(int i=0;i<k;i++)
{
    if(a[i]==1)
    {
        cout<<"yes"<<endl;
    }
    else
    {
        cout<<"no"<<endl;
    }
}

} int check(char exp1[],char expp2[]) { int i,j; for(i=0;i<3;i++) { if((exp1[i]=='b'||exp1[i]=='o')||(expp2[i]=='b'||expp2[i]=='o')) continue; else break; } //cout<<"i="<<i<<endl; if(i==3) return 1; else return 0; }