feat: 2563_count_fair_pairs

Author: upupming

.gitignore

@@ -12,3 +12,4 @@ out
 *_input.txt
 *_output.txt
 build
+target

Cargo.lock

@@ -0,0 +1,5 @@
+[workspace]
+
+members = [
+    "leetcode/残酷刷题/rs",
+]

Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "rs"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

leetcode/残酷刷题/rs/Cargo.lock

@@ -0,0 +1,75 @@
+/*
+/**
+ * @param {number[]} nums
+ * @param {number} lower
+ * @param {number} upper
+ * @return {number}
+ */
+var countFairPairs = function(nums, lower, upper) {
+    const n = nums.length
+    nums.sort((a, b) => a-b)
+    nums[n] = 1e10
+    let c = 0
+    // console.log(nums)
+    for (let i = 0; i < n; i++) {
+        let s, t
+        let l = i+1, r = n
+        // 第一个 >= lower 的地方
+        while (l < r) {
+            const mid = l+r >> 1
+            if (nums[i]+nums[mid] >= lower) r = mid
+            else l = mid+1
+        }
+        s = l
+        // 第一个 > upper 的地方
+        l = 1, r = n
+        while (l < r) {
+            const mid = l+r >> 1
+            if (nums[i]+nums[mid] > upper) r = mid
+            else l = mid+1
+        }
+        t = l
+        // 区间 [s, t)
+        c += Math.max(t-s, 0)
+        // console.log(i, s, t, t-s)
+    }
+    return c
+};
+*/
+impl Solution {
+    pub fn count_fair_pairs(nums: Vec<i32>, lower: i32, upper: i32) -> i64 {
+        let n = nums.len();
+        let mut nums = nums;
+        nums.sort();
+        nums.push(1e10 as i32);
+        let mut c = 0;
+        for i in 0..n {
+            let mut s;
+            let mut t;
+            let mut l = i + 1;
+            let mut r = n;
+            while l < r {
+                let mid = (l + r) >> 1;
+                if nums[i] + nums[mid] >= lower {
+                    r = mid;
+                } else {
+                    l = mid + 1;
+                }
+            }
+            s = l;
+            l = i + 1;
+            r = n;
+            while l < r {
+                let mid = (l + r) >> 1;
+                if nums[i] + nums[mid] > upper {
+                    r = mid;
+                } else {
+                    l = mid + 1;
+                }
+            }
+            t = l;
+            c += t - s;
+        }
+        return c as i64;
+    }
+}

leetcode/残酷刷题/rs/Cargo.toml

@@ -0,0 +1,6 @@
+fn main() {
+    println!("Hello, world!");
+
+    let a: i32 = "1";
+    panic!();
+}