Operation | Meaning |
---|---|

`V.empty()` |
Returns `true` , if `V` has no elements. Otherwise, it returns `false` . |

`V.size()` |
Returns the number of elements in `V` , i.e. $0$ or more. |

`V.push_back(e)` |
Adds an element with value `e` to the end of `V` . |

`V.pop_back()` |
Removes the last element of `V` . Calling `pop_back` on an empty vector results in undefined behavior. |

`V.clear()` |
Removes all elements from `V` , i.e. `V.size()` becomes $0$. |

`V[i]` |
Returns the element with subscript $i$, i.e. the $(i+1)$th element stored in the vector. |

`V1 = V2 ` |
Replaces the elements in vector `V1` with a copy of the elements in vector `V2` . |

`V1 == V2 ` |
Returns `true` , if `V1.size()` is equal to `V2.size()` and `V1[0] == V2[0]` , `V1[1] == V2[1]` , $\cdots$, `V1[V1.size()-1] == V2[V2.size()-1]` . Otherwise, it returns `false` . |

`V1 != V2 ` |
Returns `true` , if `V1 == V2` returns `false` . Otherwise, it returns `false` . |

Finally, it’s important to remember that the first element of a vector has subscript zero (i.e. `V[0]`

),
while the last element of the vector has subscript `V.size()`

$-1$ (i.e. `V[V.size()-1]`

).

PREVIOUSPitfalls