public class 马虎的算式 { public static void main(String[] args) { int count=0; for (int a = 1; a <= 9; a++) { for (int b = 1; b <= 9; b++) { //每次for循环前要判断前面是否有相等元素 if (a != b) for (int c = 1; c <= 9; c++) { if (b != c && a != c) for (int d = 1; d <= 9; d++) { if (a != d && b != d && c != d) for (int e = 1; e <= 9; e++) { if (a != e && b != e && c != e && d != e) { if ((a * 10 + b) * (c * 100 + d * 10 + e) == (a * 100 + d * 10 + b) * (c * 10 + e)) { count++; } } } } } } } System.out.println(count);//答案为142 }}