C++, 2D 벡터 분할 오류

Question

안녕하세요. 세분화 오류로 인해 코드 검토가 필요합니다. 내 2D 벡터에 메모리가 할당되지 않았기 때문에 그 것이지만 어떻게해야합니까?

std::vector <std::vector <std::string>> pdf_report::random_data (int num_entries, int report_type) 
{ 
    std::vector <std::vector <std::string>> printer_control; 
    int card_num_max = 999899, card_num_min = 100000; // card number 
    int vol_ent_max = 1000, vol_ent_min = 10; // volume entered 
    int vol_disp_max = 7, vol_disp_min = 0; // volume dispensed 
    int cn_type_max = 10, cn_type_min = 1; // card type 
    int charge_amt_max = 400, charge_amt_min = 2; 
    int vol_bal_max = 6000, vol_bal_min = 0; 
    int auth_num_max = 9999, auth_num_min = 1000; 
    srand (time (NULL)); // seed rand() with new values 

    switch (report_type) 
    { 
     case 1: // Report 1: Card Number, Volume Entered, Volume Dispensed 
     { 
      // fill a string array with random values 
      for (int k = 0; k < num_entries; k++) 
      { 
       int randNum = 0; 
       int randNum1 = 0; 
       int randNum2 = 0; 
       int randNum3 = 0; 

       // fill column 0 for Card Number 
       randNum = rand() % (card_num_max - card_num_min) + card_num_min; // generate random numbers inside range 
       printer_control [k][0] = int_to_str (randNum); // set string array element equal to converted int 

       // fill column 1 for Volume Entered 
       randNum1 = rand() % (vol_ent_max - vol_ent_min) + vol_ent_min; // generate random numbers inside range 
       printer_control [k][1] = int_to_str (randNum1); // set string array element equal to converted int 

       // fill column 2 for Volume Dispensed 
       randNum2 = rand() % (vol_disp_max - vol_disp_min); // generate random numbers inside range 
       randNum3 = randNum1 - randNum2; // volume dispensed could be lower than the number entered, but not higher 
       printer_control [k][2] = int_to_str (randNum3); // set string array element equal to converted int 
      } 
      break; 
     } 
    } 

    return printer_control; 
} 

나는 더 많은 경우가 있지만 일하기를 원한다면 다른 사람들에게 복사해야합니다. 도와 줘서 고마워.

Answer 1

코드에서 printer_control이 num_entries x 3의 매트릭스라고 가정합니다.

printer_control.resize (num_entries); 
for (int i=0; i<num_entries; i++) 
    printer_control[i].resize (3);