How do you write a program in c plus plus to search a number in an array?

Answer 1

The following function performs a non-recursive linear search of the given vector, returning a constant iterator to the element containing the given value. If the value does not exist, the "one-past-the-end" iterator is returned instead.

std::vector<int>::const_iterator find (int val, const std::vector<int>& v){

for (std::vector<int>::const_iterator it=v.begin(); it!=v.end(); ++it)

if (*it==val) return it;

return v.end();

}

Answer 2

Consider an integer array arr with maxnum elements stored in it. num is the number to be searched.

There are two ways of searching:

1. Linear Search: If your array is not sorted, then this is the way to go. Here you will linearly scan the array(check every element) and then display the position of the element if found.

int i, flag = 0;//flag is used to check if the number is found or not

for( i=0; i

if( arr[i] 0)

printf("The element doesn't occur in the array

Answer 3

The following function performs a non-recursive linear search of the given vector, returning a constant iterator to the element containing the given value. If the value does not exist, the "one-past-the-end" iterator is returned instead.

std::vector::const_iterator find (int val, const std::vector& v){

for (std::vector::const_iterator it=v.begin(); it!=v.end(); ++it)

if (*it==val) return it;

return v.end();

}