View Compilation Error

0_0_36528738_3221.cpp: In function 'int main()':
0_0_36528738_3221.cpp:127:17: error: 'x' was not declared in this scope
    if((1ll<<k)<=x){
                 ^
0_0_36528738_3221.cpp:128:8: error: 'i' was not declared in this scope
     a1[i]=1ll<<k;
        ^