我如何为此创建一个循环，使其在执行下一个 if 语句之前完成每个 if 语句？

Question

What I am trying to do is find if the finalWeight is divisible by 45 if so I add it into the array actualWeights then subtract the finalWeight by 45 and go on till it is no longer divisible by 45. Then goes to 25, 5 and 2.5. I just don't know how to make the loop in a way that it finishes all of 45 and then goes to the next if statement.

        if(Math.floor(finalWeight/45)){
            actualWeights.push(45);
            finalWeight -= 45;
        }else if(Math.floor(finalWeight/25)){
            actualWeights.push(25)
            finalWeight -= 25;
        }else if(Math.floor(finalWeight/10)){
            actualWeights.push(10)
            finalWeight -= 10;            
        }else if(Math.floor(finalWeight/5)){
            actualWeights.push(5)
            finalWeight -= 5;
        }else if(Math.floor(finalWeight/2.5)){
            actualWeights.push(2.5)
            finalWeight -= 2.5;
        }

Answer 1

Based on your description you want a greedy algorithm, which won't always produce an option with the least number of, in this case, weights.

To make this code DRY, we can simplify this to take in an array of weights available.

 const calculateWeights = (targetWeight, validWeights) => validWeights.reduce((ret, weight) => { ret.weights = ret.weights.concat( new Array(Math.floor(ret.remainingWeight / weight)).fill(weight) ); ret.remainingWeight %= weight; return ret; }, { remainingWeight: targetWeight, weights: [] }).weights; const finalWeight = 115; const validWeights = [45, 25, 10, 5, 2.5]; const weights = calculateWeights(finalWeight, validWeights); console.log(weights);

another way to write this, without reduce or new Array(size).fill(value) , is this

 const calculateWeights = (targetWeight, validWeights) => { const weights = []; let remainingWeight = targetWeight; // not needed, you can subtract from `targetWeight` itself since it's a copy, but usually you shouldn't modifiy inputs. for (const weight of validWeights) { while (remainingWeight >= weight) { weights.push(weight); remainingWeight -= weight; } } return weights; }; const finalWeight = 115; const validWeights = [45, 25, 10, 5, 2.5]; const weights = calculateWeights(finalWeight, validWeights); console.log(weights);

Pick whichever makes more sense/is more readable to you and others. If performance becomes an issue, then see which is faster.