Count Rectangles with Side Ratio in C++

Given sides of rectangles in and range variables first and last. The goal is to find the count of rectangles that have a ratio of their side’s length/breadth lying in the range [ first, last].

For Example

Input

rec[] = { { 200, 210 }, { 100, 50 }, { 300, 190}, {180, 200}, {300, 200}} and first = 1.0, last = 1.6

Output

Count of number of rectangles such that ratio of sides lies in the range [a,b] are: 4

Explanation

The sides that have ratio in the range [ 1.0,1.6 ] are :
{200,210}, {300,190}, {180,200}, {300,200}

Input

rec[] = { { 10,20 }, { 30, 10 }, { 100, 500}, {900, 300}, {450, 90}} and
first = 3.0, last = 4.0

Output

Count of number of rectangles such that ratio of sides lies in the range [a,b]
are: 2

Explanation

The sides that have ratio in the range [ 3.0,4.0 ] are :
{30,10}, {900,300}

Approach used in the below program is as follows −

In this approach we will take sides in the form of an array of pair<int,int>. For each pair check if the larger value/smaller value has a result which lies in the range [ first,last ]. If true then increment count of such pairs.

• Take an array rec[] of type pair<int,int>.

• Take two variables first and last for defining range.

• Function ratio_sides(pair<int, int> rec[], int total, double first, double last) takes the sides of rectangles and returns the count of number of rectangles such that ratio of sides lies in the range [a,b].

• Take the initial count as 0.

• Using a for loop traverse from i=0 to i<total.

• Extract larger value in pair rec[i] as maxi = max(rec[i].first, rec[i].second).

• Extract smaller value in pair rec[i] as mini = min(rec[i].first, rec[i].second).

• Calculate average=maxi/mini.

• If average has value in range [ first,last ], then increment count.

• At the end of the for loop return count as result..

Example

 Live Demo

#include <bits/stdc++.h>
using namespace std;
int ratio_sides(pair<int, int> rec[], int total, double first, double last){
   int count = 0;
   for (int i = 0; i < total; i++){
      double maxi = max(rec[i].first, rec[i].second);
      double mini = min(rec[i].first, rec[i].second);
      double average = maxi/mini;
      if (average >= first){
         if(average <= last){
            count++;
         }
      }
   }
   return count;
}
int main(){
   pair<int, int> rec[] = { { 200, 210 }, { 100, 50 }, { 300, 190}, {180, 200}, {300, 200}};
   int total = 5;
   double first = 1.0, last = 1.6;
   cout<<"Count of number of rectangles such that ratio of sides lies in the range [a,b] are: "<<ratio_sides(rec, total, first, last);
   return 0;
}

Output

If we run the above code it will generate the following output −

Count the number of rectangles such that ratio of sides lies in the range [a,b] are: 4