Iterate from second element of a vector in C++

This post will discuss how to iterate from the second element of a vector in C++. Assume the vector is not empty.

1. Using `std::advance` function

A simple solution is to get an iterator to the beginning of the vector and use the STL algorithm std::advance to advance the iterator by one position. Then we use that iterator as the starting position in the loop.

#include <iostream>

#include <vector>

#include <iterator>

int main()

{

std::vector<int> v = { 1, 2, 3, 4, 5 };

std::vector<int>::iterator it = v.begin();

std::advance(it, 1); // or, use `++it`

while (it != v.end())

{

std::cout << *it << ' ';

++it;

}

return 0;

}

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Output:

2 3 4 5

2. Using `std::next` or `++`, `+` operator

We can even set the starting iterator in a single line using any of the following methods:

⮚ Using std::next in C++11

for (auto it = std::next(v.begin()); it != v.end(); ++it) {

std::cout << *it << ' ';

}

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⮚ Using ++ operator

for (auto it = ++v.begin(); it != v.end(); ++it) {

std::cout << *it << ' ';

}

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⮚ Using + operator

for (auto it = v.begin() + 1; it != v.end(); ++it) {

std::cout << *it << ' ';

}

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3. Skipping the first element inside the loop

The idea is to use a normal for-loop to iterate the vector and skip the first element inside the loop, as shown below:

for (auto it = v.begin(); it != v.end(); ++it)

{

if (it != v.begin()) {

std::cout << *it << ' ';

}

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That’s all about iterating from the second element of a vector in C++.

Iterate from second element of a vector in C++

1. Using std::advance function

2. Using std::next or ++, + operator

3. Skipping the first element inside the loop

1. Using `std::advance` function

2. Using `std::next` or `++`, `+` operator