I'm new to c++ and as I'm currently learning, I'm getting myself familiar with the syntax and everything else so I created many functions that do very basic stuff and included them in main.cpp that is created by default in clion IDE. All of the functions are tested separately under main() and all of them work perfectly fine. However, when I try copy and pasting the code in a separate file that let's say I name examples.cpp as far as I know here's how I run it separately in the terminal(mac os):
make examples
./examples
and it should create the executable file and run or at least that's what I'm expecting.
Here's how main.cpp which I rename to a separate file outside clion project folder called examples.cpp looks like:
#include <iostream>
#include <vector>
#include <ctime>
#include <cstring>
using std::cout;
using std::cin;
using std::endl;
using std::string;
using std::vector;
int no_val(){
int age = 5;
cout << age << endl;
return 0;
}
double calculate_area(double width, double length){
return width * length;
}
double calculate_area_inputs(){
double width;
double length;
cout << "Enter room width: ";
cin >> width;
cout << "\nEnter room length: ";
cin >> length;
return width * length;
}
void signed_unsigned(){
int x1 = -23;
unsigned x2 = -55;
cout << x1 << " " << x2 << endl;
}
long double types(){
short int x1 = 10000;
long double x2 = 1'000'000;
long double x3 = 5e300;
short product = 5 * 5;
return product;
}
void sizes(){
cout << "char: " << sizeof(char) << endl;
cout << "string: " << sizeof(string) << endl;
cout << "int: " << sizeof(int) << endl;
cout << "float: " << sizeof(float) << endl;
cout << "double: " << sizeof(double) << endl;
cout << "short int: " << sizeof(short int) << endl;
cout << "long int: " << sizeof(long int) << endl;
cout << "long double: " << sizeof(long double) << endl;
cout << "const int: " << sizeof(const int) << endl;
}
void other_syntax(){
int x1 = 12U;
int x2 = 15L;
int x3 = 155UL;
const int x4 = 1555LL;
}
void containers(){
int abc [5];
int xyz [5] {1, 2, 3, 4, 5};
vector<int> aaa;
vector<vector<int>> bbb {{1, 2, 3}, {4, 5, 6, 7}, {8, 9, 10}};
}
void statements(){
int a = 6;
int b = 5;
if (a > b) cout << "a > b";
};
void control(int z){
if (z > 10){
cout << z;
cout << "\n" << z * 10;
}
else {
cout << "XYZ" << endl;
}
}
void more_control(){
enum Color{
red, green, blue
};
Color screen_color {red};
switch (screen_color) {
case red: cout << "red"; break;
case green: cout << "green"; break;
case blue: cout << "blue"; break;
default: "shouldn't execute";
}
}
void more_control_2(){
char expected_grade;
cout << "What grade do you expect? ";
cin >> expected_grade;
switch (expected_grade) {
case 'a': cout << "90 - 100";
break;
case 'b': cout << "80 - 90";
break;
case 'c': cout << "70 - 80";
break;
case 'd': cout << "60 - 60";
break;
default: cout << "Fail";
}
}
int conditions(int n){
return (n > 5) ? 23 : 55;
}
void initialize_vector(long int n){
time_t t1, t2;
time(&t1);
vector<int> nums(n);
time(&t2);
double duration = difftime(t2, t1);
printf ("time taken for function() %.2lf seconds.\n", duration);
}
void initialize_array(long int n){
int nums [n];
cout << "array: " << sizeof(nums) / sizeof(nums[0]) << endl;
}
void loops() {
for (int i = 0, j = 100; i <= 100, j >= 0; ++i, --j)
cout << "(" << i << ", " << j << ") ";
cout << endl;
int scores [] {30, 22, 40, 29, 5};
for (auto score: scores)
cout << score << " ";
cout << endl;
int i = 0;
while (i <= 10){
cout << i << " ";
++i;
}
cout << endl;
do {
cout << i << " ";
++i;
} while(i <= 20);
}
void strings(){
char xyz [] {"xyz"};
char xyz2 [] {"akj"};
xyz2[3] = 'p';
for (auto i: xyz2)
cout << i;
cout << endl;
char xyx [8];
strcpy(xyx, "jansasf");
for (auto i: xyx)
cout << i;
cout << endl;
char xyx2 [20];
strcpy(xyx2, "klm");
strcpy(xyx2, "zef");
strcat(xyx2, "jefomok");
for (auto i: xyx2)
cout << i;
}
void more_strings(){
char s1 [10];
for (auto i: s1)
cout << i;
char aaa [] = {"kkklllmmm"};
cout << aaa << endl;
cout << "aaa is of length: " << strlen(aaa) << endl;
string s2;
string s3 {"abcd"};
string s4 {"abcde", 2};
string s5 {3, 'X'};
cout << s2 << endl;
cout << s3 << endl;
cout << s4 << endl;
cout << s5 << endl;
}
void more_strings2(){
string pt1 {"xyx"};
string pt2 {" kkk"};
string sentence = pt1 + pt2;
cout << sentence << endl;
for (auto i: sentence)
cout << i << " ";
cout << endl;
cout << sentence.substr(4, 8) << endl;
cout << sentence.size() << endl;
cout << "Enter name: ";
string pt3;
getline(cin, pt3);
cout << pt3 << endl;
cout << "Enter name again: ";
string pt4;
getline(cin, pt4, 'a');
cout << pt4 << endl;
}
void mathematics(){
cout << "RAND_MAX on my system is: " << RAND_MAX << endl;
}
void xxx(int abc = 5){
cout << abc;
}
long double factorial(int n){
if (n == 1 || n == 0) {
return 1;
}
return n * factorial(n - 1);
}
int add_numbers(int n1, int n2){
return n1 + n2;
}
double add_numbers(double n1, double n2){
return n1 + n2;
}
void print_array(const int xxx [], size_t size) {
cout << '[';
for (size_t i = 0; i <= size; ++i)
cout << xxx[i] << ((i < size) ? " " : "");
cout << ']';
}
void swap_values(int &a, int &b){
int temp = a;
a = b; b = temp;
}
void static_example()
{
// static variable
static int count = 0;
cout << count << " ";
// value is updated and
// will be carried to next
// function calls
count++;
}
inline int add_nums(int a, int b){
return a + b;
}
int main() {
cout << add_nums(1, 5);
return 0;
}
void forward_declaration(int n){
cout << "OK: " << n;
}
The following errors and warnings occur:
c++ examples.cpp -o examples
examples.cpp:44:23: error: expected ';' at end of declaration
long double x2 = 1'000'000;
^
;
examples.cpp:73:16: error: expected ';' at end of declaration
int xyz [5] {1, 2, 3, 4, 5};
^
;
examples.cpp:75:22: error: a space is required between consecutive right angle
brackets (use '> >')
vector<vector<int>> bbb {{1, 2, 3}, {4, 5, 6, 7}, {8, 9, 10}};
^~
> >
examples.cpp:75:28: error: expected ';' at end of declaration
vector<vector<int>> bbb {{1, 2, 3}, {4, 5, 6, 7}, {8, 9, 10}};
^
;
examples.cpp:98:23: error: expected ';' at end of declaration
Color screen_color {red};
^
;
examples.cpp:103:18: warning: expression result unused [-Wunused-value]
default: "shouldn't execute";
^~~~~~~~~~~~~~~~~~~
examples.cpp:143:32: warning: relational comparison result unused
[-Wunused-comparison]
for (int i = 0, j = 100; i <= 100, j >= 0; ++i, --j)
~~^~~~~~
examples.cpp:146:9: error: definition of variable with array type needs an
explicit size or an initializer
int scores [] {30, 22, 40, 29, 5};
^
examples.cpp:146:18: error: expected ';' at end of declaration
int scores [] {30, 22, 40, 29, 5};
^
;
examples.cpp:147:10: warning: 'auto' type specifier is a C++11 extension
[-Wc++11-extensions]
for (auto score: scores)
^
examples.cpp:147:20: warning: range-based for loop is a C++11 extension
[-Wc++11-extensions]
for (auto score: scores)
^
examples.cpp:163:10: error: definition of variable with array type needs an
explicit size or an initializer
char xyz [] {"xyz"};
^
examples.cpp:163:16: error: expected ';' at end of declaration
char xyz [] {"xyz"};
^
;
examples.cpp:164:10: error: definition of variable with array type needs an
explicit size or an initializer
char xyz2 [] {"akj"};
^
examples.cpp:164:17: error: expected ';' at end of declaration
char xyz2 [] {"akj"};
^
;
examples.cpp:166:10: warning: 'auto' type specifier is a C++11 extension
[-Wc++11-extensions]
for (auto i: xyz2)
^
examples.cpp:166:16: warning: range-based for loop is a C++11 extension
[-Wc++11-extensions]
for (auto i: xyz2)
^
examples.cpp:171:10: warning: 'auto' type specifier is a C++11 extension
[-Wc++11-extensions]
for (auto i: xyx)
^
examples.cpp:171:16: warning: range-based for loop is a C++11 extension
[-Wc++11-extensions]
for (auto i: xyx)
^
examples.cpp:178:10: warning: 'auto' type specifier is a C++11 extension
[-Wc++11-extensions]
for (auto i: xyx2)
^
examples.cpp:178:16: warning: range-based for loop is a C++11 extension
[-Wc++11-extensions]
for (auto i: xyx2)
^
examples.cpp:184:10: warning: 'auto' type specifier is a C++11 extension
[-Wc++11-extensions]
for (auto i: s1)
^
examples.cpp:184:16: warning: range-based for loop is a C++11 extension
[-Wc++11-extensions]
for (auto i: s1)
^
examples.cpp:190:14: error: expected ';' at end of declaration
string s3 {"abcd"};
^
;
examples.cpp:191:14: error: expected ';' at end of declaration
string s4 {"abcde", 2};
^
;
examples.cpp:192:14: error: expected ';' at end of declaration
string s5 {3, 'X'};
^
;
examples.cpp:200:15: error: expected ';' at end of declaration
string pt1 {"xyx"};
^
;
examples.cpp:201:15: error: expected ';' at end of declaration
string pt2 {" kkk"};
^
;
examples.cpp:204:10: warning: 'auto' type specifier is a C++11 extension
[-Wc++11-extensions]
for (auto i: sentence)
^
examples.cpp:204:16: warning: range-based for loop is a C++11 extension
[-Wc++11-extensions]
for (auto i: sentence)
^
14 warnings and 16 errors generated.
make: *** [examples] Error 1
So I tried(and I'm not sure whether this is even valid):
c++ examples.cpp -std=c++11
I got less errors but it failed anyway:
examples.cpp:44:23: error: expected ';' at end of declaration
long double x2 = 1'000'000;
^
;
examples.cpp:103:18: warning: expression result unused [-Wunused-value]
default: "shouldn't execute";
^~~~~~~~~~~~~~~~~~~
examples.cpp:143:32: warning: relational comparison result unused
[-Wunused-comparison]
for (int i = 0, j = 100; i <= 100, j >= 0; ++i, --j)
~~^~~~~~
2 warnings and 1 error generated.
and here's what I get when I use std=c++20:
error: invalid value 'c++20' in '-std=c++20'
note: use 'c++98' or 'c++03' for 'ISO C++ 1998 with amendments' standard
note: use 'gnu++98' or 'gnu++03' for 'ISO C++ 1998 with amendments and GNU
extensions' standard
note: use 'c++11' for 'ISO C++ 2011 with amendments' standard
note: use 'gnu++11' for 'ISO C++ 2011 with amendments and GNU extensions'
standard
note: use 'c++14' for 'ISO C++ 2014 with amendments' standard
note: use 'gnu++14' for 'ISO C++ 2014 with amendments and GNU extensions'
standard
note: use 'c++17' for 'ISO C++ 2017 with amendments' standard
note: use 'gnu++17' for 'ISO C++ 2017 with amendments and GNU extensions'
standard
note: use 'c++2a' for 'Working draft for ISO C++ 2020' standard
note: use 'gnu++2a' for 'Working draft for ISO C++ 2020 with GNU extensions'
standard
What is the proper way of running c++ files in the terminal and in general? why is it failing in the terminal and the same code runs perfectly fine in the IDE? I'm sorry if this sounds stupid and thanks in advance.
I don't know what you are trying to do with your code, but you need to compile with C++17:
g++ -std=c++17 examples.cpp -o examples
./examples
I get 2 other warnings
One warning is here:
default: "shouldn't execute";
You probably meant:
default:
cout << "shouldn't execute";
break;
Second warning is here:
for (int i = 0, j = 100; i <= 100, j >= 0; ++i, --j)
i <= 100 is left unused and only j >= 0 will be considered because of the comma operator. You need to write:
i <= 100 && j >= 0