求三个数的中间值

#include <stdio.h>
#include <math.h>
int mid(int a,int  b,int c)
{
return  a + b + c - ((((a + b) + abs(a - b))/ 2 + c)+ abs(((a + b) + abs(a - b))/ 2 - c))/ 2 
- ((((a + b) - abs(a - b)) / 2 + c)- abs(((a + b) - abs(a - b)) / 2 - c)) / 2;
}


int main()
{
printf("%d \n", mid(3, 4, 1));
printf("%d \n", mid(1, 1, 3));
printf("%d \n", mid(5, 9, 3));
printf("%d \n", mid(0, 3, -1));
return 0;
}

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