例 void main {intx=12y=0,a=0.b=0; switch(x) case switch(y) i case 0: a++, break case 1: b++. break case 2: a++: b++. break case 3 a++: b++ rIn ntf( na=%d, b=%d, a, b) 运行结果:a=2,b=1例 void main() { int x=1,y=0,a=0,b=0; switch(x) { case 1: switch(y) { case 0: a++; break; case 1: b++; break; } case 2: a++;b++; break; case 3: a++;b++; } printf(“\na=%d,b=%d”,a,b); } 运行结果：a=2,b=1