the following code fills the vector with 10 values in first for loop.in second for loop i want the elements of vector to be printed. The output is till the cout statement before the j loop.Gives error of vector subscript out of range.
#include "stdafx.h" #include "iostream" #include "vector" using namespace std; int _tmain(int argc, _TCHAR * argv[]) { vector<int> v; cout << "Hello India" << endl; cout << "Size of vector is: " << v.size() << endl; for (int i = 1; i <= 10; ++i) { v.push_back(i); } cout << "size of vector: " << v.size() << endl; for (int j = 10; j > 0; --j) { cout << v[j]; } return 0; } 3 Answers
Regardless of how do you index the pushbacks your vector contains 10 elements indexed from 0 (0, 1, ..., 9). So in your second loop v[j] is invalid, when j is 10.
This will fix the error:
for(int j = 9;j >= 0;--j) { cout << v[j]; } In general it's better to think about indexes as 0 based, so I suggest you change also your first loop to this:
for(int i = 0;i < 10;++i) { v.push_back(i); } Also, to access the elements of a container, the idiomatic approach is to use iterators (in this case: a reverse iterator):
for (vector<int>::reverse_iterator i = v.rbegin(); i != v.rend(); ++i) { std::cout << *i << std::endl; } v has 10 element, the index starts from 0 to 9.
for(int j=10;j>0;--j) { cout<<v[j]; // v[10] out of range } you should update for loop to
for(int j=9; j>=0; --j) // ^^^^^^^^^^ { cout<<v[j]; // out of range } Or use reverse iterator to print element in reverse order
for (auto ri = v.rbegin(); ri != v.rend(); ++ri) { std::cout << *ri << std::endl; } this type of error usually occur when you try to access data through the index in which data data has not been assign. for example
//assign of data in to array for(int i=0; i<10; i++){ arr[i]=i; } //accessing of data through array index for(int i=10; i>=0; i--){ cout << arr[i]; } the code will give error (vector subscript out of range) because you are accessing the arr[10] which has not been assign yet.
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