计算1到M（M为偶数）之间的奇数之和和偶数之和
#include
#define M 100
main()
{ int a,b,c,i;
clrscr();
a=0;c=0;
for(i=1;___(1)___;i+=2)
{ a+=i;
___(2)___;
c+=b; }
printf("sum of evens is %d\n",c);
printf("sum of odds is %d\n",a);
}
结果··SUM OF EVENS IS 2500
SUM OF ODDS IS 2500