Given two integers **M1** and **M2** representing the slope of two lines intersecting at a point, the task is to find the angle between these two lines.

**Examples:**

Input:M_{1}= 1.75, M_{2}= 0.27Output:45.1455 degrees

Input:M_{1}= 0.5, M_{2}= 1.75Output:33.6901 degrees

**Approach: **If **θ** is the angle between the two intersecting lines, then the angle **θ** can be calculated by:

tanθ = |(M

_{2}– M_{1}) / (1 + M_{1}* M_{2})|

=> θ = tan^{-1}( |(M_{2}– M_{1}) / (1 + M_{1}* M_{2})| )

Follow the steps below to solve the problem:

- Initialize a variable, say
**A**, to store the value of the angle between the two lines. - Using the above formula, find the value of
**tan(A)****A**by taking the tan inverse of the angle. - Convert the angle from radian to degrees.
- Print the value of
**A**in degrees as the result.

Below is the implementation of the above approach:

## C++

`// C++ program for the above approach` `#include <bits/stdc++.h>` `using` `namespace` `std;` `#define PI 3.14159265` `// Function to find the` `// angle between two lines` `void` `findAngle(` `double` `M1, ` `double` `M2)` `{` ` ` `// Store the tan value of the angle` ` ` `double` `angle = ` `abs` `((M2 - M1)` ` ` `/ (1 + M1 * M2));` ` ` `// Calculate tan inverse of the angle` ` ` `double` `ret = ` `atan` `(angle);` ` ` `// Convert the angle from` ` ` `// radian to degree` ` ` `double` `val = (ret * 180) / PI;` ` ` `// Print the result` ` ` `cout << val;` `}` `// Driver Code` `int` `main()` `{` ` ` `double` `M1 = 1.75, M2 = 0.27;` ` ` `findAngle(M1, M2);` ` ` `return` `0;` `}` |

## Java

`// Java program for the above approach` `import` `java.util.*;` `class` `GFG` `{` ` ` `static` `double` `PI = ` `3.14159265` `;` ` ` `// Function to find the` ` ` `// angle between two lines` ` ` `static` `void` `findAngle(` `double` `M1, ` `double` `M2)` ` ` `{` ` ` ` ` `// Store the tan value of the angle` ` ` `double` `angle = Math.abs((M2 - M1) / (` `1` `+ M1 * M2));` ` ` `// Calculate tan inverse of the angle` ` ` `double` `ret = Math.atan(angle);` ` ` `// Convert the angle from` ` ` `// radian to degree` ` ` `double` `val = (ret * ` `180` `) / PI;` ` ` `// Print the result` ` ` `System.out.println(val);` ` ` `}` ` ` `// Driver Code` ` ` `public` `static` `void` `main(String []args)` ` ` `{` ` ` `double` `M1 = ` `1.75` `, M2 = ` `0.27` `;` ` ` `findAngle(M1, M2);` ` ` `}` `}` `// This code is contributed by rrrtnx.` |

## Python3

`# Python3 program for the above approach` `from` `math ` `import` `atan` `# Function to find the` `# angle between two lines` `def` `findAngle(M1, M2):` ` ` `PI ` `=` `3.14159265` ` ` ` ` `# Store the tan value of the angle` ` ` `angle ` `=` `abs` `((M2 ` `-` `M1) ` `/` `(` `1` `+` `M1 ` `*` `M2))` ` ` `# Calculate tan inverse of the angle` ` ` `ret ` `=` `atan(angle)` ` ` `# Convert the angle from` ` ` `# radian to degree` ` ` `val ` `=` `(ret ` `*` `180` `) ` `/` `PI` ` ` `# Print the result` ` ` `print` `(` `round` `(val, ` `4` `))` `# Driver Code` `if` `__name__ ` `=` `=` `'__main__'` `:` ` ` `M1 ` `=` `1.75` ` ` `M2 ` `=` `0.27` ` ` `findAngle(M1, M2)` ` ` `# This code is contributed by mohit kumar 29.` |

## C#

`// C# program for the above approach` `using` `System;` `class` `GFG` `{` ` ` `static` `double` `PI = 3.14159265;` ` ` `// Function to find the` ` ` `// angle between two lines` ` ` `static` `void` `findAngle(` `double` `M1, ` `double` `M2)` ` ` `{` ` ` ` ` `// Store the tan value of the angle` ` ` `double` `angle = Math.Abs((M2 - M1) / (1 + M1 * M2));` ` ` `// Calculate tan inverse of the angle` ` ` `double` `ret = Math.Atan(angle);` ` ` `// Convert the angle from` ` ` `// radian to degree` ` ` `double` `val = (ret * 180) / PI;` ` ` `// Print the result` ` ` `Console.Write(val);` ` ` `}` ` ` `// Driver Code` ` ` `public` `static` `void` `Main()` ` ` `{` ` ` `double` `M1 = 1.75, M2 = 0.27;` ` ` `findAngle(M1, M2);` ` ` `}` `}` `// This code is contributed by ukasp.` |

## Javascript

`<script>` ` ` `// JavaScript program` ` ` `// for the above approach` ` ` `const PI = 3.14159265;` ` ` `// Function to find the` ` ` `// angle between two lines` ` ` `function` `findAngle(M1, M2) {` ` ` `// Store the tan value of the angle` ` ` `var` `angle = Math.abs((M2 - M1) / (1 + M1 * M2));` ` ` `// Calculate tan inverse of the angle` ` ` `var` `ret = Math.atan(angle);` ` ` `// Convert the angle from` ` ` `// radian to degree` ` ` `var` `val = (ret * 180) / PI;` ` ` `// Print the result` ` ` `document.write(val.toFixed(4));` ` ` `}` ` ` `// Driver Code` ` ` `var` `M1 = 1.75,` ` ` `M2 = 0.27;` ` ` `findAngle(M1, M2);` ` ` `</script>` |

**Output:**

45.1455

**Time Complexity:** O(1)**Auxiliary Space: **O(1)

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