C program to print result of a series

Q: program to print total of 1-2+3-4+5-6+7....

#include

#include

void main()

{

int k,sum=0;

clrscr();

for(k=1;k<=10;k++)

{

if(k%2==1)

sum=sum+k;

else

sum=sum-k;

}

printf("sum=%d ",sum);

getch();

}