# 颠倒的价牌 小李的店里专卖其它店中下架的样品电视机,可称为:样品电视专卖店。 其标价都是4位数字(即千元不等)。 小李为了标价清晰、方便,使用了预制的类似数码管的标价签,只要用颜色笔涂数字就可以了(参见图片)。 ![](https://img-blog.csdnimg.cn/20200315215554485.png) 这种价牌有个特点,对一些数字,倒过来看也是合理的数字。如:1 2 5 6 8 9 0 都可以。这样一来,如果牌子挂倒了,有可能完全变成了另一个价格,比如:1958 倒着挂就是:8561,差了几千元啊!! 当然,多数情况不能倒读,比如,1110 就不能倒过来,因为0不能作为开始数字。 有一天,悲剧终于发生了。某个店员不小心把店里的某两个价格牌给挂倒了。并且这两个价格牌的电视机都卖出去了! 庆幸的是价格出入不大,其中一个价牌赔了2百多,另一个价牌却赚了8百多,综合起来,反而多赚了558元。 请根据这些信息计算:赔钱的那个价牌正确的价格应该是多少? ## aop ### before ```cpp #include using namespace std; ``` ### after ```cpp ``` ## 答案 ```cpp int main() { int num1[7] = {0, 1, 2, 5, 6, 8, 9}; int num2[7] = {0, 1, 2, 5, 9, 8, 6}; int profit1[1111][2]; int profit2[1111][2]; int before_reverse; int after_reverse; int i = 0; int j = 0; for (int a = 1; a < 7; a++) { for (int b = 0; b < 7; b++) { for (int c = 0; c < 7; c++) { for (int d = 0; d < 7; d++) { before_reverse = num1[a] * 1000 + num1[b] * 100 + num1[c] * 10 + num1[d]; after_reverse = num2[d] * 1000 + num2[c] * 100 + num2[b] * 10 + num2[a]; if (after_reverse - before_reverse > -300 && after_reverse - before_reverse < -200) { profit1[i][0] = before_reverse; profit1[i][1] = after_reverse - before_reverse; i++; } else if (after_reverse - before_reverse > 800 && after_reverse - before_reverse < 900) { profit1[j][0] = before_reverse; profit2[j][1] = after_reverse - before_reverse; j++; } } } } } int answer = 0; for (int a = 0; a < i; a++) { for (int b = 0; b < j; b++) { if (profit1[a][1] + profit2[b][1] == 558) { answer = profit1[a][0]; } } } cout << answer << endl; return 0; } ``` ## 选项 ### A ```cpp int main() { int num1[7] = {0, 1, 2, 5, 6, 8, 9}; int num2[7] = {0, 1, 2, 5, 9, 8, 6}; int profit1[1111][2]; int profit2[1111][2]; int before_reverse; int after_reverse; int i = 0; int j = 0; for (int a = 1; a < 7; a++) { for (int b = 0; b < 7; b++) { for (int c = 0; c < 7; c++) { for (int d = 0; d < 7; d++) { before_reverse = num1[a] * 1000 + num1[b] * 100 + num1[c] * 10 + num1[d]; after_reverse = num2[d] * 1000 + num2[c] * 100 + num2[b] * 10 + num2[a]; if (after_reverse - before_reverse > -300 && after_reverse - before_reverse < -200) { profit1[i][0] = before_reverse; profit1[i][1] = after_reverse - before_reverse; i++; } else if (after_reverse - before_reverse > 800 && after_reverse - before_reverse < 900) { profit1[j][0] = before_reverse; profit2[j][1] = after_reverse - before_reverse; j++; } } } } } int answer = 0; for (int a = 0; a < i; a++) { for (int b = 0; b < j; b++) { if (profit1[a][1] + profit2[b][1] == 558) { answer = profit1[b][1]; } } } cout << answer << endl; return 0; } ``` ### B ```cpp int main() { int num1[7] = {0, 1, 2, 5, 6, 8, 9}; int num2[7] = {0, 1, 2, 5, 9, 8, 6}; int profit1[1111][2]; int profit2[1111][2]; int before_reverse; int after_reverse; int i = 0; int j = 0; for (int a = 1; a < 7; a++) { for (int b = 0; b < 7; b++) { for (int c = 0; c < 7; c++) { for (int d = 0; d < 7; d++) { before_reverse = num1[a] * 1000 + num1[b] * 100 + num1[c] * 10 + num1[d]; after_reverse = num2[d] * 1000 + num2[c] * 100 + num2[b] * 10 + num2[a]; if (after_reverse - before_reverse > -300 && after_reverse - before_reverse < -200) { profit1[i][0] = before_reverse; profit1[i][1] = after_reverse - before_reverse; i++; } else if (after_reverse - before_reverse > 800 && after_reverse - before_reverse < 900) { profit1[j][0] = before_reverse; profit2[j][1] = after_reverse - before_reverse; j++; } } } } } int answer = 0; for (int a = 0; a < i; a++) { for (int b = 0; b < j; b++) { if (profit1[a][1] + profit2[b][1] == 558) { answer = profit1[b][0]; } } } cout << answer << endl; return 0; } ``` ### C ```cpp int main() { int num1[7] = {0, 1, 2, 5, 6, 8, 9}; int num2[7] = {0, 1, 2, 5, 9, 8, 6}; int profit1[1111][2]; int profit2[1111][2]; int before_reverse; int after_reverse; int i = 0; int j = 0; for (int a = 1; a < 7; a++) { for (int b = 0; b < 7; b++) { for (int c = 0; c < 7; c++) { for (int d = 0; d < 7; d++) { before_reverse = num1[a] * 1000 + num1[b] * 100 + num1[c] * 10 + num1[d]; after_reverse = num2[d] * 1000 + num2[c] * 100 + num2[b] * 10 + num2[a]; if (after_reverse - before_reverse > -300 && after_reverse - before_reverse < -200) { profit1[i][0] = before_reverse; profit1[i][1] = after_reverse - before_reverse; i++; } else if (after_reverse - before_reverse > 800 && after_reverse - before_reverse < 900) { profit1[j][0] = before_reverse; profit2[j][1] = after_reverse - before_reverse; j++; } } } } } int answer = 0; for (int a = 0; a < i; a++) { for (int b = 0; b < j; b++) { if (profit1[a][1] + profit2[b][1] == 558) { answer = profit1[0][b]; } } } cout << answer << endl; return 0; } ```