// 定义牙膏 牙刷 牙膏盒分别的价格 let toothpaste = 0;let toothbrush = 0;let toothpastebox = 0;// 定义sum用来存储几种情况let sum = 0;//第一层循环 循环牙膏买多少for (let i = 0; i <= 20; i++){toothpaste = 5 * i;// 二层循环 循环牙刷的数量for (let j = 0; j <= 50; j++){toothbrush = 2 * j;// 三层循环,循环牙膏盒的数量for (let k = 0; k < 7; k++){toothpastebox = 15 * k;// 将这些数量加起来符合等于100的条件 就对sum+1if (toothpaste + toothbrush + toothpastebox == 100){sum++;}}}} // 输出多少种情况console.log("正好花完100元共有"+sum+"种情况");