import assert from 'node:assert/strict';
const A=[[1,2],[3,4]],B=[[5,6],[7,8]],N=2,K=2;
const fresh=()=>({a:null,b:null,acc:0,count:0});
let grid=Array.from({length:N},()=>Array.from({length:N},fresh));
const expected=[[[5,0],[0,0]],[[19,6],[15,0]],
                [[19,22],[43,18]],[[19,22],[43,50]]];
const token=(value,k)=>({value,k});
for(let t=0;t<K+2*N-2;t++) {
 const next=grid.map(r=>r.map(p=>({...p})));
 for(let i=0;i<N;i++) for(let j=0;j<N;j++) {
  const ka=t-i,kb=t-j;
  const a=j?grid[i][j-1].a:(ka>=0&&ka<K?token(A[i][ka],ka):null);
  const b=i?grid[i-1][j].b:(kb>=0&&kb<K?token(B[kb][j],kb):null);
  const p=next[i][j];p.a=a;p.b=b;
  if(a&&b){assert.equal(a.k,b.k);assert.equal(a.k,p.count);
   p.acc+=a.value*b.value;p.count++;}
 }
 grid=next;
 assert.deepEqual(grid.map(r=>r.map(p=>p.acc)),expected[t]);
}
assert.deepEqual(grid.map(r=>r.map(p=>p.count)),[[2,2],[2,2]]);
console.log('Schedule lab passed');