求大神帮看下错那了，新手学C

Question

# include <stdio.h>
# include <math.h>
int main (void)
{
int a = 1;
int b = 2;
int c = 3;
double delta;
double x1;
double x2;
delta = b*b - 4*a*c;

if (delta > 0)
{
x1 = (-b + sqrt(delta)) / (2*a);
x2 = (-b - sqrt(delta)) / (2*a);
printf(“该一元二次方程有两个解，x1 = %f,x2 = %f\n”,x1,x2);
}
else if (delta == 0)
{
x1 = ( - b ) / ( 2*a );
x2 = x1;
printf(“该一元二次方程有一个唯一解, x1 = x2 = %f\n”,x1);
}
else
{
printf(“无解”);
}

Answer 1

1. 引号问题，改成英语输入法的“”
2. 最后丢了个}

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Answer 2

#include <stdio.h>
#include <math.h>
#include <stdlib.h>
int main (void)
{
int a = 1;
int b = 2;
int c = 3;
double delta;
double x1;
double x2;
delta = b*b - 4*a*c;

if (delta > 0)
{
x1 = (-b + sqrt(delta)) / (2*a);
x2 = (-b - sqrt(delta)) / (2*a);
printf("该一元二次方程有两个解，x1 = %f,x2 = %f\n",x1,x2);
system("pause");
}
else if (delta == 0)
{
x1 = ( - b ) / ( 2*a );
x2 = x1;
printf("该一元二次方程有一个唯一解, x1 = x2 = %f\n",x1);
system("pause");
}
else
{
printf("无解");
system("pause");
}
}

Answer 3

你确定上面那个是你的源程序复制过来的？如果是那么首先printf里面的引号要改成英文输入的引，还有就是用double类型算了开放和除法，会在一定程度上丢失精度号，===程序的最后还要加一个}，再就是程序没有输入具体的x的值所以程序直接会输出了无解后还差个