var obj = [
{ a: 1, b: 2, c: 3 },
{ a: 4, b: 5, c: 6 },
{ a: 7, b: 8, c: 9 },
{ a: 2, b: 3, c: 10 }
];
the total block is added from the bottom, that is, first, sum4=a4+b4+c5=2+3+10=15, is the last in the total, and the second to last is sum3=sum4+c3=15+9=24;, the second is sum2=sum3+c2=24+6=30;, the first is sum1=sum2+c1=30+3=33;, what should I say?