三角形相似性验证程序：几何算法实现教程

#include <iostream>

#include <cmath>

using namespace std;

int main() {

   double x1 = 0, y1 = 0, x2 = 3, y2 = 0, x3 = 0, y3 = 4; //coordinates of first triangle (x1, y1), (x2, y2), (x3, y3)

   double p1 = 0, q1 = 0, p2 = 6, q2 = 0, p3 = 0, q3 = 8; //coordinates of second triangle (p1, q1), (p2, q2), (p3, q3)

   // calculate the distance between the coordinates of the first triangle

   double dist1 = sqrt(pow((x2 - x1), 2) + pow((y2 - y1), 2));

   double dist2 = sqrt(pow((x3 - x2), 2) + pow((y3 - y2), 2));

   double dist3 = sqrt(pow((x1 - x3), 2) + pow((y1 - y3), 2));

   // calculate the distance between the coordinates of the second triangle

   double dist4 = sqrt(pow((p2 - p1), 2) + pow((q2 - q1), 2));

   double dist5 = sqrt(pow((p3 - p2), 2) + pow((q3 - q2), 2));

   double dist6 = sqrt(pow((p1 - p3), 2) + pow((q1 - q3), 2));

   // calculate the ratio of the length of the triangle

   double ratio1 = dist1/dist4;

   double ratio2 = dist2/dist5;

   double ratio3 = dist3/dist6;

   // check if the ratio of all three pairs of sides of the triangle are same, we are using SSS criteria

   if ((ratio1 == ratio2) && (ratio2 == ratio3)) {

      cout

<h3>输出</h3>

<pre class="brush:php;toolbar:false;">The two triangles are similar.

#include <iostream>

using namespace std;

bool check_aa(int a1,int a2,int a3,int a4,int a5,int a6){

   if((a1==a4 || a1==a5 || a1==a6) && (a2==a4 || a2==a5 || a2==a6))

   return true;

   else

   return false;

}

int main(){

   // Input:  the angles of the triangles

   double a1 = 30, a2 = 60, a3 = 90; //angles of triangle A

   double a4 = 60, a5 = 90, a6 = 30; //angles of triangle B

   bool similar= check_aa(a1,a2,a3,a4,a5,a6);

   if (similar)

      cout

<h3>输出</h3>

<pre class="brush:php;toolbar:false;">The two triangles are similar.