Question

c++编程问题

#include "math.h"
#include "stdio.h“
main()
{
float a,b,c,p,s;
printf("please input the date!\n");
scanf("%f，%f，%f",&a,&b,&c);
p=(a+b+c)/2;
s=sqrt(p*(p-a)*(p-b)*(p-c));
printf("s=%f\n",s);
}
求三角形面积为啥现实有错？\Untitled1.c|2|#include expects "FILENAME" or <FILENAME>|
\Untitled1.c||In function `int main()':|
\Untitled1.c|6|error: `printf' was not declared in this scope|
\Untitled1.c|7|error: `scanf' was not declared in this scope|
||=== Build finished: 3 errors, 0 warnings ===|

Answer 1

\Untitled1.c|2|#include expects "FILENAME" or <FILENAME>|：第二行#include "stdio.h“，后面那个引号要英文引号。。\Untitled1.c||In function `int main()':|：main()函数默认返回值类型为int，而你没有返回int类型数据，要么程序最后加个return 1;要么把main()改为void main()，即返回值类型为空。。\Untitled1.c|6|error: `printf' was not declared in this scope|
\Untitled1.c|7|error: `scanf' was not declared in this scope|：因为前面"stdio.h"出错，等于没有加进这个头文件，就找不到printf和scanf这两个函数。。

Answer 2

#include "math.h"
#include "stdio.h"main()
{
float a,b,c,p,s;
printf("please input the date!\n");
scanf("%f，%f，%f",&a,&b,&c);
p=(a+b+c)/2;
s=sqrt(p*(p-a)*(p-b)*(p-c));
printf("s=%f\n",s);
} 英文状态的双引号（黑体部分）被你写成中文双引号了