A common error when writing code

Lab stage to do exercises, among which, change bug title:

#include <iostream> #include <vector>int main (int, char**) {std::vector<int>** Pprandomdata = Distributerandomint (unsigned int i=0; i<1000; i++) {if (Pprandomdata[i]) {std::cout << "Elements in [" & lt;< i << "]:"; for (unsigned int k=0; K<pprandomdata[i]->size (); k++) {std::cout << pprandomdata[i]->at (k) << "";} Std::cout << Std::endl;}} Delete[] Pprandomdata;return 0;} std::vector<int>** distributerandomint (int vMod) {assert (VMod > 0);std::vector<int> **ppcontainer; Ppcontainer = new Std::vector<int>*[vmod];srand (0); for (int i=0; i<1000; i++) {int randomnum = rand (); STD:: vector<int> *pcontainer = ppcontainer[randomnum%vmod];if (Pcontainer = NULL) {pcontainer = new std::vector<int& Gt;;}pcontainer->push_back (randomnum);} return Ppcontainer;}

This question has been tested at several test centers:

1 when you first apply for an array pointer, be sure to initialize each member of the array

2 assignment and reference between pointer field pointers

The difference between 3= and = =

4 memory leaks: releasing pointers and releasing pointers

5 This migic number

Changes such as the following:

#include <assert.h>//add#include <iostream> #include <vector>std::vector<int>** Distributerandomint (int vMod); const INT total = 100;int main (int, char**) {std::vector<int>** Pprandomdata = Distributerandomint (+);//for (unsigned int i=0; i<1000; i++) for (unsigned int i=0; i<100; i++)//100 migic number{i F (Pprandomdata[i]) {std::cout << "Elements in [" << I << "]:", for (unsigned int k=0; K<pprandomdata[i]->size (); k++) {std::cout << pprandomdata[i]->at (k) << "";} Std::cout << Std::endl;}} for (int i=0; i<100; ++i) {if (Pprandomdata[i]! = NULL) Delete pprandomdata[i];//releases the memory for each piece of application in the array}delete[] pprandomdata; return 0;} std::vector<int>** distributerandomint (int vMod) {assert (VMod > 0);std::vector<int> **ppcontainer; Ppcontainer = new Std::vector<int>*[vmod];for (int i=0; i<vmod; ++i)//Initialize array pointer {ppcontainer[i] = NULL;} Srand (0); for (int i=0; i<1000; i++) {int randomnum = rand ();//std::vector<int> *pcontainer = ppcontainer[randomnum%vmod];std::vector<int>*& PContainer = ppContainer[ randomnum%vmod];//pointer reference, to change the value of the pointer//if (Pcontainer = null) if (Pcontainer = = null)//= = = Difference {//pcontainer = new std::vector& Lt;int>;pcontainer = new Std::vector<int>;} Pcontainer->push_back (randomnum);} return Ppcontainer;}

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A common error when writing code