三角形面积计算(命令行参数)

Question

Answer 1

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int main(int argc, char *argv[])
{
    if(argc != 4) //windows下argv[0]是命令本身。
    {
        printf("Non triangle.\n");
        return 1;
    }
    
    float a=atof(argv[1]);
    float b=atof(argv[2]);
    float c=atof(argv[3]);
    
    if(a+b<=c || a+c<=b || b+c <=a)
    {
        printf("Non triangle.");
        return -1;
    }
    
    float p=(a+b+c)/2;
    double area = sqrt(p*(p-a)*(p-b)*(p-c));        
    
    printf("area=%lf\n",area);
    return 0;
}