# Python | Find mismatch item on same index in two list

Given two list of integers, the task is to find the index at which the element of two list doesn’t match.

```Input:
Input1 = [1, 2, 3, 4]
Input2 = [1, 5, 3, 6]

Output: [1, 3]
Explanation:
At index=1 we have 2 and 5 and at index=3
we have 4 and 6 which mismatches.
```

Below are some ways to achieve this task.

Method #1: Using Iteration

 `# Python code to find the index at which the  ` `# element of two list doesn't match. ` ` `  `# List initialisation ` `Input1 ``=` `[``1``, ``2``, ``3``, ``4``] ` `Input2 ``=` `[``1``, ``5``, ``3``, ``6``] ` ` `  `# Index initialisation ` `y ``=` `0` ` `  `# Output list intialisation ` `Output ``=` `[]  ` ` `  `# Using iteration to find ` `for` `x ``in` `Input1: ` `    ``if` `x !``=` `Input2[y]: ` `        ``Output.append(y) ` `    ``y ``=` `y ``+` `1` ` `  `# Printing output ` `print``(Output) `

Output:

```[1, 3]
```

Method #2: Using list Comprehension and zip

 `# Python code to find the index at which the  ` `# element of two list doesn't match. ` ` `  `# List initialisation ` `Input1 ``=` `[``1``, ``2``, ``3``, ``4``] ` `Input2 ``=` `[``1``, ``5``, ``3``, ``6``] ` ` `  `# Using list comprehension and zip  ` `Output ``=` `[Input2.index(y) ``for` `x, y ``in` `       ``zip``(Input1, Input2) ``if` `y !``=` `x] ` ` `  `# Printing output ` `print``(Output) `

Output:

```[1, 3]
```

Method #3: Using Enumerate

 `# Python code to find the index at which the  ` `# element of two list doesn't match. ` ` `  `# List initialisation ` `Input1 ``=` `[``1``, ``2``, ``3``, ``4``] ` `Input2 ``=` `[``1``, ``5``, ``3``, ``6``] ` ` `  `# Using list comprehension and enumerate ` `Output ``=` `[index ``for` `index, elem ``in` `enumerate``(Input2) ` `                           ``if` `elem !``=` `Input1[index]] ` ` `  `# Printing output ` `print``(Output) `

Output:

```[1, 3]
```

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