c语言输入一个坐标(x,y,z)判断该点在哪个象限

Question

#include <stdio.h>
int main()
{
double x y z;
printf("Input x,y,z :\n");
scanf("%lf%lf%lf,&x,&y,&z);
if(x>=0)
if(y>=0)
if(z>=0) printf("the first quadrant\n");
else printf("the fifth quadrant\n");
else
if(z>=0) printf("the fourth quadrant\n");
else printf("the eighth quadrant\n");
else
if(y>=0)
if(z>=0) printf("the second quadrant\n");
else printf("the sixth quadrant\n");
else
if(z>=0) printf("the third quadrant\n");
else printf("the seventh quadrant\n");
return 0;
}

求助 这是我写的 但是编译显示
D:\vc++6.0_win8\Common\MSDev98\Bin\Cpp12.cpp(10) : error C2181: illegal else without matching if
D:\vc++6.0_win8\Common\MSDev98\Bin\Cpp12.cpp(11) : error C2181: illegal else without matching if
D:\vc++6.0_win8\Common\MSDev98\Bin\Cpp12.cpp(14) : error C2181: illegal else without matching if
执行 cl.exe 时出错.
求指点!!!!!

Answer 1

最好if-else都加上大括号

scanf("---"这里少了半个双引号：定义的变量用逗号分隔开

#include <stdio.h>
int main()
{
double x, y, z;//////////
printf("Input x,y,z :\n");
scanf("%lf%lf%lf",&x,&y,&z);////////
if (x >= 0){
if (y >= 0){
if (z >= 0) printf("the first quadrant\n");
else printf("the fifth quadrant\n");
}
else{
if (z >= 0) printf("the fourth quadrant\n");
else printf("the eighth quadrant\n");
}
}
else{
if (y >= 0){
if (z >= 0) printf("the second quadrant\n");
else printf("the sixth quadrant\n");
}
else{
if (z >= 0) printf("the third quadrant\n");
else printf("the seventh quadrant\n");
}
}
return 0;
}