编程:读入三个点的坐标,确定他们是否在一条线上

发布网友发布时间：2023-12-28 06:05

共2个回答

热心网友时间：2024-12-12 18:38

没指明用什么语言，用C写了。
#include <stdio.h>
#include <math.h>

#define jing  0.000001

int main(){
    double x1, y1, x2, y2, x3, y3;
    double k, b, t;
    int flag = 0;

    //输入3个坐标:
    printf("Input point A:x, y:");
    scanf("%lf, %lf", &x1, &y1);

    printf("Input point b:x, y:");
    scanf("%lf, %lf", &x2, &y2);

    printf("Input point C:x, y:");
    scanf("%lf, %lf", &x3, &y3);


    if (fabs(x2-x1)<jing) {//平行于x轴，斜率为0，只需判断x3
      if (fabs(x2-x3) < jing)
        flag = 1;
    } else {
      k = (y2-y1)/(x2-x1); //计算斜率
      b = y1-k*x1;
      t = k*x3 + b;
      if (fabs(y3-t) < jing)
        flag = 1;
    }

    if (flag == 1)
        printf("三点在一条直线上。\n");
    else
        printf("三点不在一条直线上。\n");

    return 0;
}

热心网友时间：2024-12-12 18:39

#include<stdio.h>
#include<math.h>
int main()
{
float x1, x2, x3, y1, y2, y3;
//输入3个坐标:
printf("Input point A:x, y:");
scanf("%lf, %lf", &x1, &y1);
printf("Input point b:x, y:");
scanf("%lf, %lf", &x2, &y2);
printf("Input point C:x, y:");
scanf("%lf, %lf", &x3, &y3);
if(x1=x3||x1=x2||x2=x3) {
if(x1=x2=x3) printf("在同一直线上。\n")
else printf("不在同一直线上。\n");
}
else{
if ((y1 - y2) / (x1 - x2) == (y2 - y3) / (x2 - x3))
printf("在同一直线上。\n");
else printf("不在同一直线上。\n");
}
return 0;
}