Javascript Data Structure Tutorial - Javascript Sequential Search

Sequential Search is to loop from the start of an array to the end of it.

Example


function seqSearch(arr, data) { /* w w  w  .  j  a v a 2  s.  c  o m*/
    for (var i = 0; i < arr.length; ++i) { 
        if (arr[i] == data) { 
            return true; 
        } 
    } 
    return false; 
} 
function printArray(arr) { 
    for (var i = 0; i < arr.length; ++i) { 
        console.log(arr[i] + " "); 
        if (i % 10 == 9) { 
            console.log("\n"); 
        } 
    } 
    if (i % 10 != 0) { 
        console.log("\n"); 
    } 
} 
var nums = []; 
for (var i = 0; i < 100; ++i) { 
    nums[i] = Math.floor(Math.random() * 101); 
} 
printArray(nums); 
var num = 14; 
console.log(); 
if (seqSearch(nums, num)) { 
    console.log(num + " is in the array."); 
} else { 
    console.log(num + " is not in the array."); 
} 
console.log(); 
printArray(nums);

Example 2

We can write the sequential search function to return the position where a match is found.


function seqSearch(arr, data) { //  ww  w . j av  a 2  s  .c o  m
    for (var i = 0; i < arr.length; ++i) { 
        if (arr[i] == data) { 
            return i; 
        } 
    } 
    return -1; 
} 
function printArray(arr) { 
    for (var i = 0; i < arr.length; ++i) { 
        console.log(arr[i] + " "); 
        if (i % 10 == 9) { 
            console.log("\n"); 
        } 
    } 
    if (i % 10 != 0) { 
        console.log("\n"); 
    } 
} 

var nums = []; 
for (var i = 0; i < 100; ++i) { 
    nums[i] = Math.floor(Math.random() * 101); 
} 
var num = 14; 
console.log(); 
var position = seqSearch(nums, num); 
if (position > -1) { 
    console.log(num + " is in the array at position " + position); 
} else { 
    console.log(num + " is not in the array."); 
} 
console.log(); 
printArray(nums);