c++ - Structured Data: Nesting Triangles using structs and calculating -

problem description:write code of function takes triangle input , returns area. expected figure out how access data, understanding abstract data types defined.you may use method compute area vertices

you required write function:

function name : cal_area

this function has 1 parameter

triangle atriangle: contains 3 vertices of triangle in x-y plane. expected figure out how access data. function should following

it should return area of triangle "atriangle" float.

well question need fill following

//-----include required headers here----- #include <iostream.h> #include <cmath> //-----end of headers-----  //-----don't change/delete structs----- struct vertex{ float x; float y; };  struct triangle{ vertex vertices[3]; }; struct linesegment {   point endpoint1;   point endpoint2;  };  //-----structs end here   //-----add new functions here(if any)----- double eval (linesegment line, point p) {  point p_a = p - line.endpoint1;  point l_dir = line.endpoint2 - line.endpoint1;    return p_a.x * l_dir.y - p_a.y * l_dir.x;  }   void maketrianglecounterclockwise(triangle & t)   {    linesegment ab = {t.vertices[1], t.vertices[0]};    if ( eval(ab,t.vertices[2]) < 0.0) {      swap(t.vertices[0],t.vertices[1]);     }     }      //-----new functions end here-----        float cal_area(triangle atriangle) {     //write solution below line        return (-1);      //dont write below line      } 

i tried write fuction went wrong pls help

i think you’re trying this:

float cal_area(triangle atriangle) {    float area;     area = (atriangle.vertices[1].x - atriangle.vertices[0].x) *           (atriangle.vertices[2].y - atriangle.vertices[1].y) -           (atriangle.vertices[1].y - atriangle.vertices[0].y) *           (atriangle.vertices[2].x - atriangle.vertices[1].x);     if (area < 0.0f) {       return -area / 2.0f;    } else {       return area / 2.0f;    } }