20131002国庆作业第三章例3-1,3-2,3-3

#include<stdio.h>
int main(void)
{
int  mynumber=38;
int  yournumber;

printf("Input your number:");
scanf("%d",&yournumber);
if(yournumber==mynumber)
printf("Ok!you are right!\n");
else
if(yournumber>mynumber)
printf("Sorry!your number is bigger than my number!\n");
else
printf("Sorry!your number is smaller than my number!\n");

return 0;
}

#include<stdio.h>
int main(void)
{
int number;

printf("Enter a number:");
scanf("%d",&number);
if(number%2==0){
printf("The number is even.\n");
}
else{
printf("The number is odd.\n");
}

return 0;
}

#include<stdio.h>
int main(void)
{
int count,i,n;
double grade,total;

printf("Enter n:");
scanf("%d",&n);
total=0;
count=0;
for(i=1;i<=n;i++){
printf("Enter  grade#%d:",i);
scanf("%lf",&grade);
total=total+grade;
if(grade<60){
count++;
}
}
printf("Grade average=%.2f\n",total/n);
printf("Number of failures=%d\n",count);

return 0;
}