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POOperation over iterators in c++
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copied!<p>I have some problem in translating some rows of code from ANSI C and arrays, to C++ with vectors.</p> <p>To operate iteratively along the element of the array, in ANSI C, I wrote:</p> <pre><code>int i; struct Sys{ double *v; }; Sys sys; sys.v = malloc(10*sizeof(double)); //initialize the array with some values... {...} for (i = 5; i < 10; i++){ //overwrite the cumulative sum starting from position 4 sys.v[i] = sys.v[i] + function_that_return_a_double(i); } </code></pre> <p>Now, I wont to translate in C++ with vectors. Here is my trial.</p> <pre><code>Sys { vector<double> v; }; Sys sys; sys.v.resize(10); // initialize the vector with some values... {...} for (vector<double>::iterator it = sys.v.begin() + 5; it != sys.v.end(); ++it){ //yyy k = k+1; tmp = function_that_return_a_double(k); *it = *it + tmp; //xxx } </code></pre> <p>But I get the following error:</p> <pre><code>code.cpp:xxx: error: name lookup of ‘it’ changed for ISO ‘for’ scoping code.cpp:xxx: note: (if you use ‘-fpermissive’ G++ will accept your code) </code></pre> <p>If i complile with -fpermissive, I get:</p> <pre><code>code.cpp:xxx: warning: name lookup of ‘it’ changed for ISO ‘for’ scoping code.cpp:yyy: warning: using obsolete binding at ‘it’ </code></pre> <p>I don't undenstand if this is the right way to use the iterators and STD:vector</p> <p>I hope you can solve my doubts,</p> <p>Cheers,</p> <p>Al.</p> <p>PS: I corrected the declaration of v in the c++ case. v is not a pointer! PPS: The code snippet is fine!! see below. </p>

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