1.
#include <stdio.h>
int main(void)
{
int i = 10;
while(i<=20)
{
printf("%d ",i++);
}
}
//do-while
#include <stdio.h>
int main(void)
{
int i = 10;
do
{
printf("%d ",i++);
}
while (i<=20);
}
2.// do-while
#include <stdio.h>
int main(void)
{
int i = 10;
do
{
if(i%2 == 0)
printf("%d ",i);
i++;
}
while (i<=20);
}
//while
#include <stdio.h>
int main(void)
{
int i = 10;
while(i<=20)
{
if(i%2 == 0)
printf("%d ",i);
i++;
}
}
3.
#include <stdio.h>
int main(void)
{
int a;
int a1= 0;
printf("输入一个正整数:");
scanf("%d",&a);
while(a!=0)
{
a1 = a1*10+a%10;
a = a/10;
}
printf("%d\n",a1);
}
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