poj2301beat the spread

/*题意就是第一个是两数和，第二个是差，求那两个数。。话说题确实不难，不过我第一次用的循环，感觉就不对，事实真不对。原来大神是这么做的
哎呀，数学不行真不行，有压力啊，和差相加，和差相减 然后除以二*/

#include<stdio.h>int main(){    int sum, dif, t;    scanf_s("%d", &t);    while (t--)    {        scanf_s("%d %d", &sum, &dif);        if ((sum + dif) % 2 == 1 || dif>sum)            printf_s("impossible\n");        else            printf_s("%d %d\n", (sum + dif) / 2, (sum - dif) / 2);    }    return 0;}

/*Description
Superbowl Sunday is nearly here. In order to pass the time waiting for the half-time commercials and wardrobe malfunctions, the local hackers have organized a betting pool on the game. Members place their bets on the sum of the two final scores, or on the absolute difference between the two scores.
Given the winning numbers for each type of bet, can you deduce the final scores?

Input
The first line of input contains n, the number of test cases. n lines follow, each representing a test case. Each test case gives s and d, non-negative integers representing the sum and (absolute) difference between the two final scores.

Output
For each test case, output a line giving the two final scores, largest first. If there are no such scores, output a line containing "impossible". Recall that football scores are always non-negative integers.

Sample Input

2
40 20
20 40

Sample Output

30 10
impossible
*/