#!/usr/bin/python3
# https://theweeklychallenge.org/blog/perl-weekly-challenge-250/#TASK1
#
# Task 1: Smallest Index
# ======================
#
# You are given an array of integers, @ints.
#
# Write a script to find the smallest index i such that i mod 10 == $ints[i]
# otherwise return -1.
#
## Example 1
##
## Input: @ints = (0, 1, 2)
## Output: 0
##
## i=0: 0 mod 10 = 0 == $ints[0].
## i=1: 1 mod 10 = 1 == $ints[1].
## i=2: 2 mod 10 = 2 == $ints[2].
## All indices have i mod 10 == $ints[i], so we return the smallest index 0.
#
## Example 2
##
## Input: @ints = (4, 3, 2, 1)
## Output: 2
##
## i=0: 0 mod 10 = 0 != $ints[0].
## i=1: 1 mod 10 = 1 != $ints[1].
## i=2: 2 mod 10 = 2 == $ints[2].
## i=3: 3 mod 10 = 3 != $ints[3].
## 2 is the only index which has i mod 10 == $ints[i].
#
## Example 3
##
## Input: @ints = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]
## Output: -1
## Explanation: No index satisfies i mod 10 == $ints[i].
#
############################################################
##
## discussion
##
############################################################
#
# Walk the array from the start to the end, return once
# i mod 10 == $ints[i]. In the end, return -1 if no entry
# satisfied the condition.

def smallest_index(ints: list):
    print("Input: (", ", ".join([str(x) for x in ints]), ")")
    for i in range(len(ints)):
        if i % 10 == ints[i]:
            print(f"Output: {i}")
            return
    print("Output: -1")

smallest_index([0, 1, 2])
smallest_index([4, 3, 2, 1])
smallest_index([1, 2, 3, 4, 5, 6, 7, 8, 9, 0])