Language: C

#include<stdio.h>
        #define int long long
        #define fo(i,l,u)   for(i=l;i<u;i++)
        #define MOD         1000000007





        //int n;
    /*    void multiply(int n,int arr[][n] , int ary[][n]){
            int mat[n][n],i,j,k;
            fo(i,0,n){
                fo(j,0,n){
                    mat[i][j]=0;
                    fo(k,0,n){
                        mat[i][j]=(mat[i][j]+arr[i][k]*ary[k][j])%MOD;
                    }
                }
            }
            fo(i,0,n){
                fo(j,0,n){
                    //cout<<mat[i][j]<<" ";
                    arr[i][j]=mat[i][j];
                }
            }
            //cout<<endl;
        }

     */

        signed main()
        { int i,j,x,d,k,n,K;
      scanf("%ld%ld",&n,&K);
            int arr[n][n];
            fo(i,0,n){
                fo(j,0,n){
                scanf("%ld",&x);
                arr[i][j]=x;
                }
            }
            //cout<<K<<endl;
            int ans[n][n];
            fo(i,0,n){
                fo(j,0,n){
                    ans[i][j]=0;
                }
            }
            fo(i,0,n){
                ans[i][i]=1;
            }





            while(K>0){

              /*  fo(i,0,n){
                            fo(j,0,n){
                                cout<<ans[i][j]<<" ";
                                //arr[i][j]=mat[i][j];
                            }
                            cout<<endl;
                        }*/



                if(K%2==1){
                    //multiply(n,ans,arr);


                    int mat[n][n];
                        fo(i,0,n){
                            fo(j,0,n){
                                mat[i][j]=0;
                                fo(k,0,n){
                                    mat[i][j]=(mat[i][j]+ans[i][k]*arr[k][j])%MOD;
                                    //cout<<mat[i][]
                               = }
                               // cout<<mat[i][j]<<" ";
                            }
                            //cout<<endl;
                        }
                        fo(i,0,n){
                            fo(j,0,n){
                                //cout<<mat[i][j]<<" ";
                                ans[i][j]=mat[i][j];
                            }
                        }


                }

                // cout<<arr[0][0]<<endl;

                int mat[n][n];

                        fo(i,0,n){
                            fo(j,0,n){
                                mat[i][j]=0;
                                fo(k,0,n){
                                    mat[i][j]=(mat[i][j]+arr[i][k]*arr[k][j])%MOD;
                                }
                            }
                        }
                        fo(i,0,n){
                            fo(j,0,n){
                                //cout<<mat[i][j]<<" ";
                                arr[i][j]=mat[i][j];
                            }
                        }



             //   multiply(n,arr,arr);





                K/=2;
            }
            x=0;
            fo(i,0,n){
                fo(j,0,n){
                    x=(x+ans[i][j])%MOD;
                }
            }
            printf("%ld",x);

            return 0;
        }

Compiler output:
main.c: In function 'main':
main.c:80:32: error: expected expression before '=' token
   80 |                                = }
      |                                ^