如何修复c中与结构相关的错误？

Question

我用c-写了这个代码：

#include <stdio.h>
#include <conio.h>

struct chemical_elements {
    char element_name[100];
    char element_symbol[10];
    int atomic_number;
    int atomic_mass;
};

void main() {
    int i;
    chemical_elements elements[118];
    char elements_name[120][20]={" ","Hydrogen","Helium","Lithium","Beryllium","Boron","Carbon","Nitrogen","Oxygen","Fluorine","Neon","Sodium","Magnesium","Aluminum","Silicon","Phosphorus","Sulfur","Chlorine","Argon","Potassium","Calcium","Scandium","Titanium","Vanadium","Chromium","Manganese","Iron","Cobalt","Nickel","Copper","Zinc","Gallium","Germanium","Arsenic","Selenium","Bromine","Krypton","Rubidium","Strontium","Yttrium","Zirconium","Niobium","Molybdenum","Technetium","Ruthenium","Rhodium","Palladium","Silver","Cadmium","Indium","Tin","Antimony","Tellurium","Iodine","Xenon","Cesium","Barium","Lanthanum","Cerium","Praseodymium","Neodymium","Promethium","Samarium","Europium","Gadolinium","Terbium","Dysprosium","Holmium","Erbium","Thulium","Ytterbium","Lutetium","Hafnium","Tantalum","Tungsten","Rhenium","Osmium","Iridium","Platinum","Gold","Mercury","Thallium","Lead","Bismuth","Polonium","Astatine","Radon","Francium","Radium","Actinium","Thorium","Protactinium","Uranium","Neptunium","Plutonium","Americium","Curium","Berkelium","Californium","Einsteinium","Fermium","Mendelevium","Nobelium","Lawrencium","Rutherfordium","Dubnium","Seaborgium","Bohrium","Hassium","Meitnerium","Darmstadtium","Roentgenium","Copernicium","Nihonium","Flerovium","Moscovium","Livermorium","Tennessine","Oganesson", " "};
    for (i=1;i<=118;i++) {
        elements[i].atomic_number=i;
        elements[i].element_name=elements_name[i];
    }       
    getch();
}

我做它是为了告诉元素电子配置，但是当我在编写代码之间签入时，在编译它时，我发现它给出了以下错误-：

new5.c(13): error C2065: 'chemical_elements': undeclared identifier
new5.c(13): error C2146: syntax error: missing ';' before identifier 'elements'
new5.c(13): error C2065: 'elements': undeclared identifier
new5.c(13): error C2109: subscript requires array or pointer type
new5.c(16): error C2065: 'elements': undeclared identifier
new5.c(16): error C2109: subscript requires array or pointer type
new5.c(17): error C2065: 'elements': undeclared identifier
new5.c(17): error C2109: subscript requires array or pointer type

我有什么办法解决这个问题吗？

Answer 1

与其在名称和原子序号中复制，不如用这些值初始化数组。

struct chemical_elements {
    const char *element_name;
    const char *element_symbol;
    int atomic_number;
    double atomic_mass;
};

const struct chemical_elements elements[] = {
  { "Hydrogen", "H",  1, 1.0079 }, 
  { "Helium",   "He", 2, 4.0026 },
  ...
  { "Oganesson", "Og", 118, 294 },
}

const size_t chemical_elements_n = sizeof chemical_elements / chemical_elements[0];

我看不出.atomic_number成员有什么理由。下面考虑一下，并使用数组索引作为原子序数。

struct chemical_elements_alt {
    const char *element_name;
    const char *element_symbol;
    double atomic_mass;
};

const struct chemical_elements_alt elements[] = {
  { "Neutron", "Nu",  1.00867 }, 
  { "Hydrogen", "H", 1.0079 }, 
  { "Helium",   "He", 4.0026 },
  ...
  { "Oganesson", "Og",  294 },
}