# Minimum cost to make two strings same

Given four integers **a**, **b**, **c**, **d** and two strings **S1** and **S2** of equal length, which consist only of the characters **‘2’**, **‘1’** and **‘0’**.

- Converting
**‘1’**to**‘2’**or vice versa costs**a**. - Converting
**‘2’**to**‘3’**or vice versa costs**b**. - Converting
**‘3’**to**‘1’**or vice versa costs**c**. - Deleting the
**i**character from^{th}**both**the strings costs**d**.

The task is to find the minimum cost to make both the strings equal in configuration.**Examples:**

Input:s1 = “121”, s2 = “223”, a = 2, b = 3, c = 4, d = 10Output:6

Change the first character from ‘1’ to ‘2’ which costs 2.

Change the third character from ‘3’ to ‘1’ which costs 4.Input:s1 = ‘222’, s2 = ‘111’, a = 20, b = 30, c = 40, d = 1Output:3

Delete all characters which costs 3 which is the minimum possible.

**Approach:**

- Iterate in the string, and if
**s1[i] = s2[i]**then perform no operation. - If the
**s1[i] = ‘1’**and**s2[i] = ‘2’**then perform the minimum cost operation from the following:- Delete
**s1[i]**and**s2[i]**which costs**d**. - Change
**‘1’**to**‘2’**which costs**a** - Change
**‘1’**to**‘3’**and then**‘3’**to**‘2’**which costs**b + c**.

- Delete
- If the
**s1[i] = ‘2’**and**s2[i] = ‘3’**then perform the minimum cost operation from the following:- Delete
**s1[i]**and**s2[i]**which costs**d**. - Change
**‘2’**to**‘3’**which costs**b**. - Change
**‘2’**to**‘1’**and then**‘1’**to**‘3’**which costs**a + c**.

- Delete
- If the
**s1[i] = ‘3’**and**s2[i] = ‘1’**then perform the minimum cost operation from the following:- Delete
**s1[i]**and**s2[i]**which costs**d**. - Change
**‘3’**to**‘1’**which costs**c**. - Change
**‘3’**to**‘2’**and then**‘2’**to**‘1’**which costs**b + a**.

- Delete

Below is the implementation of the above approach:

## C++

`// C++ implementation of the approach` `#include <bits/stdc++.h>` `using` `namespace` `std;` `// Function to return the minimum cost to make the` `// configuration of both the strings same` `int` `findCost(string s1, string s2,` ` ` `int` `a, ` `int` `b, ` `int` `c, ` `int` `d, ` `int` `n)` `{` ` ` `int` `cost = 0;` ` ` `// Iterate and find the cost` ` ` `for` `(` `int` `i = 0; i < n; i++) {` ` ` `if` `(s1[i] == s2[i])` ` ` `continue` `;` ` ` `else` `{` ` ` `// Find the minimum cost` ` ` `if` `((s1[i] == ` `'1'` `&& s2[i] == ` `'2'` `)` ` ` `|| (s2[i] == ` `'1'` `&& s1[i] == ` `'2'` `))` ` ` `cost += min(d, min(a, b + c));` ` ` `else` `if` `((s1[i] == ` `'2'` `&& s2[i] == ` `'3'` `)` ` ` `|| (s2[i] == ` `'2'` `&& s1[i] == ` `'3'` `))` ` ` `cost += min(d, min(b, a + c));` ` ` `else` `if` `((s1[i] == ` `'1'` `&& s2[i] == ` `'3'` `)` ` ` `|| (s2[i] == ` `'1'` `&& s1[i] == ` `'3'` `))` ` ` `cost += min(d, min(c, a + b));` ` ` `}` ` ` `}` ` ` `return` `cost;` `}` `// Driver Code` `int` `main()` `{` ` ` `string s1 = ` `"121"` `;` ` ` `string s2 = ` `"223"` `;` ` ` `int` `a = 2, b = 3, c = 4, d = 10;` ` ` `int` `n = s1.size();` ` ` `cout << findCost(s1, s2, a, b, c, d, n);` ` ` `return` `0;` `}` |

## Java

`// Java implementation of the approach` `class` `GFG` `{` ` ` `// Function to return the minimum cost to make the` `// configuration of both the strings same` `static` `int` `findCost(String s1, String s2,` ` ` `int` `a, ` `int` `b, ` `int` `c,` ` ` `int` `d, ` `int` `n)` `{` ` ` `int` `cost = ` `0` `;` ` ` `// Iterate and find the cost` ` ` `for` `(` `int` `i = ` `0` `; i < n; i++)` ` ` `{` ` ` `if` `(s1.charAt(i) == s2.charAt(i))` ` ` `continue` `;` ` ` `else` ` ` `{` ` ` `// Find the minimum cost` ` ` `if` `((s1.charAt(i) == ` `'1'` `&& s2.charAt(i) == ` `'2'` `) ||` ` ` `(s2.charAt(i) == ` `'1'` `&& s1.charAt(i) == ` `'2'` `))` ` ` `cost += Math.min(d, Math.min(a, b + c));` ` ` `else` `if` `((s1.charAt(i) == ` `'2'` `&& s2.charAt(i) == ` `'3'` `) ||` ` ` `(s2.charAt(i) == ` `'2'` `&& s1.charAt(i) == ` `'3'` `))` ` ` `cost += Math.min(d, Math.min(b, a + c));` ` ` `else` `if` `((s1.charAt(i) == ` `'1'` `&& s2.charAt(i) == ` `'3'` `) ||` ` ` `(s2.charAt(i) == ` `'1'` `&& s1.charAt(i) == ` `'3'` `))` ` ` `cost += Math.min(d, Math.min(c, a + b));` ` ` `}` ` ` `}` ` ` `return` `cost;` `}` `// Driver Code` `public` `static` `void` `main(String[] args)` `{` ` ` `String s1 = ` `"121"` `;` ` ` `String s2 = ` `"223"` `;` ` ` `int` `a = ` `2` `, b = ` `3` `, c = ` `4` `, d = ` `10` `;` ` ` `int` `n = s1.length();` ` ` `System.out.println(findCost(s1, s2, a, b, c, d, n));` `}` `}` `// This code is contributed by Code_Mech.` |

## Python3

`# Python 3 implementation of the approach` `# Function to return the minimum cost to make` `# the configuration of both the strings same` `def` `findCost(s1, s2, a, b, c, d, n):` ` ` `cost ` `=` `0` ` ` `# Iterate and find the cost` ` ` `for` `i ` `in` `range` `(n):` ` ` `if` `(s1[i] ` `=` `=` `s2[i]):` ` ` `continue` ` ` `else` `:` ` ` ` ` `# Find the minimum cost` ` ` `if` `((s1[i] ` `=` `=` `'1'` `and` `s2[i] ` `=` `=` `'2'` `) ` `or` ` ` `(s2[i] ` `=` `=` `'1'` `and` `s1[i] ` `=` `=` `'2'` `)):` ` ` `cost ` `+` `=` `min` `(d, ` `min` `(a, b ` `+` `c))` ` ` `elif` `((s1[i] ` `=` `=` `'2'` `and` `s2[i] ` `=` `=` `'3'` `) ` `or` ` ` `(s2[i] ` `=` `=` `'2'` `and` `s1[i] ` `=` `=` `'3'` `)):` ` ` `cost ` `+` `=` `min` `(d, ` `min` `(b, a ` `+` `c))` ` ` `elif` `((s1[i] ` `=` `=` `'1'` `and` `s2[i] ` `=` `=` `'3'` `) ` `or` ` ` `(s2[i] ` `=` `=` `'1'` `and` `s1[i] ` `=` `=` `'3'` `)):` ` ` `cost ` `+` `=` `min` `(d, ` `min` `(c, a ` `+` `b))` ` ` `return` `cost` `# Driver Code` `if` `__name__ ` `=` `=` `'__main__'` `:` ` ` `s1 ` `=` `"121"` ` ` `s2 ` `=` `"223"` ` ` `a ` `=` `2` ` ` `b ` `=` `3` ` ` `c ` `=` `4` ` ` `d ` `=` `10` ` ` `n ` `=` `len` `(s1)` ` ` `print` `(findCost(s1, s2, a, b, c, d, n))` `# This code is contributed by` `# Surendra_Gangwar` |

## C#

`// C# implementation of the approach` `using` `System;` `class` `GFG` `{` ` ` `// Function to return the minimum cost to make the` `// configuration of both the strings same` `static` `int` `findCost(` `string` `s1, ` `string` `s2,` ` ` `int` `a, ` `int` `b, ` `int` `c, ` `int` `d, ` `int` `n)` `{` ` ` `int` `cost = 0;` ` ` `// Iterate and find the cost` ` ` `for` `(` `int` `i = 0; i < n; i++)` ` ` `{` ` ` `if` `(s1[i] == s2[i])` ` ` `continue` `;` ` ` `else` ` ` `{` ` ` `// Find the minimum cost` ` ` `if` `((s1[i] == ` `'1'` `&& s2[i] == ` `'2'` `)` ` ` `|| (s2[i] == ` `'1'` `&& s1[i] == ` `'2'` `))` ` ` `cost +=Math.Min(d,Math.Min(a, b + c));` ` ` `else` `if` `((s1[i] == ` `'2'` `&& s2[i] == ` `'3'` `)` ` ` `|| (s2[i] == ` `'2'` `&& s1[i] == ` `'3'` `))` ` ` `cost +=Math.Min(d,Math.Min(b, a + c));` ` ` `else` `if` `((s1[i] == ` `'1'` `&& s2[i] == ` `'3'` `)` ` ` `|| (s2[i] == ` `'1'` `&& s1[i] == ` `'3'` `))` ` ` `cost +=Math.Min(d,Math.Min(c, a + b));` ` ` `}` ` ` `}` ` ` `return` `cost;` `}` `// Driver Code` `public` `static` `void` `Main()` `{` ` ` `string` `s1 = ` `"121"` `;` ` ` `string` `s2 = ` `"223"` `;` ` ` `int` `a = 2, b = 3, c = 4, d = 10;` ` ` `int` `n = s1.Length;` ` ` `Console.WriteLine(findCost(s1, s2, a, b, c, d, n));` `}` `}` `// This Code is Contributed by Code_Mech.` |

## Javascript

`<script>` `// javascript implementation of the approach` ` ` `// Function to return the minimum cost to make the` `// configuration of both the strings same` `function` `findCost( s1, s2 ,a, b, c, d, n)` `{` ` ` `var` `cost = 0;` ` ` `// Iterate and find the cost` ` ` `for` `(` `var` `i = 0; i < n; i++)` ` ` `{` ` ` `if` `(s1[i] == s2[i])` ` ` `continue` `;` ` ` `else` ` ` `{` ` ` `// Find the minimum cost` ` ` `if` `((s1[i] == ` `'1'` `&& s2[i] == ` `'2'` `)` ` ` `|| (s2[i] == ` `'1'` `&& s1[i] == ` `'2'` `))` ` ` `cost +=Math.min(d,Math.min(a, b + c));` ` ` `else` `if` `((s1[i] == ` `'2'` `&& s2[i] == ` `'3'` `)` ` ` `|| (s2[i] == ` `'2'` `&& s1[i] == ` `'3'` `))` ` ` `cost +=Math.min(d,Math.min(b, a + c));` ` ` `else` `if` `((s1[i] == ` `'1'` `&& s2[i] == ` `'3'` `)` ` ` `|| (s2[i] == ` `'1'` `&& s1[i] == ` `'3'` `))` ` ` `cost +=Math.min(d,Math.min(c, a + b));` ` ` `}` ` ` `}` ` ` `return` `cost;` `}` `// Driver Code` ` ` `var` `s1 = ` `"121"` `;` ` ` `var` `s2 = ` `"223"` `;` ` ` `var` `a = 2, b = 3, c = 4, d = 10;` ` ` `var` `n = s1.length;` ` ` `document.write(findCost(s1, s2, a, b, c, d, n));` ` ` ` ` `// This code is contributed by bunnyram19.` `</script>` |

**Output:**

6