#include <stdio.h> void main() { int a=1,

Question

#include <stdio.h>
void main()
{
int a=1,b=0;
do {
switch ( a )
{
case 1: ​b=1;break;
case 2: ​b=2;break;
default : ​b=0;
}
b=a+b;
} while( !b );
printf( "a=%d,b=%d", a, b );
}输出什么呢？