Algorithms: Searching Tutorials and Code Examples - Page 6

Jump Search in C++

Jump search skips fixed-size blocks in a sorted sequence, then scans the candidate block..

cpp

int jump_search(const std::vector<int>& a, int target) {
    alg_require(a.size() <= 1000000);
    int n = (int)a.size();
    alg_require(((n >= 0) && (n <= 1000000)));
    alg_require(((int)a.size() == n));
    int step = 1;
    while ((step <= (n / step))) {
        step = alg_add(step, 1);
    }
    int start = 0;
    int end = alg_min(step, n);
    while (((start < n) && (a[alg_sub(end, 1)] < target))) {

Nov 15, 2026 C++

Algorithms: Searching

Jump Search in C#

Jump search skips fixed-size blocks in a sorted sequence, then scans the candidate block..

csharp

    static int jump_search(ReadOnlySpan<int> a, int target) {
        checked {
            int n = a.Length;
            alg_require(((n >= 0) && (n <= 1000000)));
            alg_require((a.Length == n));
            int step = 1;
            while ((step <= (n / step))) {
                step = (step + 1);
            }
            int start = 0;
            int end = Math.Min(step, n);
            while (((start < n) && (a[(end - 1)] < target))) {

Nov 15, 2026 csharp

Algorithms: Searching

Jump Search in PHP

Jump search skips fixed-size blocks in a sorted sequence, then scans the candidate block..

php

function jump_search(array $a, int $target): int {
    alg_require(array_is_list($a));
    $n = count($a);
    alg_require((($n >= 0) && ($n <= 1000000)));
    alg_require((count($a) == $n));
    $step = 1;
    while (($step <= intdiv($n, $step))) {
        $step = alg_add($step, 1);
    }
    $start = 0;
    $end = min($step, $n);
    while ((($start < $n) && ($a[alg_sub($end, 1)] < $target))) {

Nov 15, 2026 PHP

Algorithms: Searching

Linear Search in PHP

Scan the input from left to right until the target is found.

php

function linear_search(array $a, int $target): int {
    alg_require(array_is_list($a));
    $n = count($a);
    alg_require((($n >= 0) && ($n <= 1000000)));
    alg_require((count($a) == $n));
    $i = 0;
    while (($i < $n)) {
        if (($a[$i] == $target)) {
            return $i;
        }
        $i = alg_add($i, 1);
    }

Nov 15, 2026 PHP

Algorithms: Searching

Upper Bound in Java

A boundary search finds an insertion position in a sorted array, including arrays with repeated values.

java

    static int upper_bound(int[] a, int target) {
        java.util.Objects.requireNonNull(a, "a");
        int n = a.length;
        alg_require(((n >= 0) && (n <= 1000000)));
        alg_require((a.length == n));
        int lo = 0;
        int hi = n;
        int mid = 0;
        while ((lo < hi)) {
            mid = Math.addExact(lo, (Math.subtractExact(hi, lo) / 2));
            if ((a[mid] <= target)) {
                lo = Math.addExact(mid, 1);

Nov 15, 2026 Java