diff --git a/2364_count_number_of_bad_pairs/Cargo.lock b/2364_count_number_of_bad_pairs/Cargo.lock new file mode 100644 index 0000000..ce3e6ad --- /dev/null +++ b/2364_count_number_of_bad_pairs/Cargo.lock @@ -0,0 +1,7 @@ +# This file is automatically @generated by Cargo. +# It is not intended for manual editing. +version = 4 + +[[package]] +name = "count_number_of_bad_pairs" +version = "0.1.0" diff --git a/2364_count_number_of_bad_pairs/Cargo.toml b/2364_count_number_of_bad_pairs/Cargo.toml new file mode 100644 index 0000000..a02f178 --- /dev/null +++ b/2364_count_number_of_bad_pairs/Cargo.toml @@ -0,0 +1,6 @@ +[package] +name = "count_number_of_bad_pairs" +version = "0.1.0" +edition = "2024" + +[dependencies] diff --git a/2364_count_number_of_bad_pairs/src/lib.rs b/2364_count_number_of_bad_pairs/src/lib.rs new file mode 100644 index 0000000..c6578c4 --- /dev/null +++ b/2364_count_number_of_bad_pairs/src/lib.rs @@ -0,0 +1,23 @@ +pub struct Solution; + +impl Solution { + pub fn count_bad_pairs(nums: Vec) -> i64 { + let mut groups = std::collections::HashMap::::new(); + + for (index, num) in nums.iter().enumerate() { + let index_sub_num = index as i32 - *num; + groups + .entry(index_sub_num) + .and_modify(|count| *count += 1) + .or_insert(1); + } + + let total_comb = Solution::count_pairs(&(nums.len() as i64)); + let same_comb: i64 = groups.values().map(Solution::count_pairs).sum(); + total_comb - same_comb + } + + fn count_pairs(n: &i64) -> i64 { + n * (n - 1) / 2 + } +}