#include <stdio.h> #include <stdlib.h> #include <string.h> const int ARRAY_LENGTH = 5; // #define ARRAY_LENGTH 5 void printarray(int* myarray, int length) { for (int i =0; i < length; i++) printf("%i, ", myarray[i]); printf("\n"); } int main(int argc, char** argv) { int a[ARRAY_LENGTH] = { 1, 2, 3, 4, 5 }; int b[ARRAY_LENGTH] = { 5, 4, 3, 2, 1 }; int* p = malloc(sizeof(int) * 15); for (int i = 0; i < 15; i++) p[i] = i; int arglengths[argc]; for (int i = 0; i < argc; i++) arglengths[i] = strlen(argv[i]); p = realloc(p, sizeof(int) * 20); printarray(a, ARRAY_LENGTH); printarray(b, ARRAY_LENGTH); printarray(p, 20); printarray(arglengths, argc); free(p); }

Dynamic memory allocation

have you tried youtube? there are tons of videos there.

Its std byte ++ something...i forgot please help me anyone

how do i convert a pointer into a float, and then back into a pointer? eg TEX * tex; // ... tex = blah; floatArray.push_back({0, FLOAT_TRUE, tex}); // ... auto data = floatArray.back(); if (data.isTex == FLOAT_TRUE) { setTex((TEX*)data.tex); }

Is there any disadvantage to use this ..?

#include <stdio.h> int main() { float num1,num2; float value; char op; printf("Enter an operator [d = /, m = *, a = +, s = - ]: "); scanf("%c",&op); printf("Enter a number: "); scanf("%f", &num1); printf("Enter another number: "); scanf("%f", &num2); if (op=='d') { value = num1/num2; printf("Answer = %f", value); } else if (op == 'm') { value = num1*num2; printf("Answer = %f", value); } else if (op == 'a') { value = num1+num2; printf("Answer = %f", value); } else if (op=='s') { value = num1-num2; printf("Answer = %f", value); } else printf("Please try again..."); return 0; }

Here's a program to find largest from 3 numbers, No syntax errors in the code, but it doesn't work properly. #include <stdio.h> #include <stdlib.h> int main() { int n1,n2,n3,max; printf(" Input 3 values you want to compare\n"); scanf("%d %d %d", &n1, &n2, &n3); if((n1>n2)&&(n1>n2)) max = n1; else if((n2>n1)&&(n2>n3)) max = n2; else max - n3; printf(" largest value is %d", max); return 0; }

else max - n3 is not assigning n3 to max change that to else max = n3 Location: in the first if statement block

Hello, what is __LINE__ in C? i found it on a source in GitHub

They are just preprocessor macros. _ _LINE_ _ - Current line number _ _FILE_ _ - Current file name _ _TIME_ _ - The time at which the current file was compiled _ _DATE_ _ - The date the file was compiled _ _func_ _ - Name of the current function.

Write a c program to input an admission number, marks of a module and display admission number with grade. The grade is assigned as follows. Marks >=75 A Marks 65-75 B Marks 55-65 C Marks 45-55 S Marks <45 F #include <stdio.h> int main() { int adnum,marks; char grade; printf("Enter your admission number "); scanf("%d",&adnum); printf("Enter your marks "); scanf("%d",&marks); if (marks >= 75) grade == "A"; else if (marks >= 65) grade == "B"; else if (marks >= 55) grade == "C"; else if (marks >= 45) grade == "S"; else grade == "F"; printf("your admission number is %d and grade is %c",adnum,grade); return 0; } Grade isn't print correctly, anyone can solve it?

Use ' ' instead of " " for your grades. Like 'A' instead of "A" And use = instead of ==. This is the 2nd time you are doing the same mistake. Learn the difference between = (assignment) and == (equality comparison)

How do I take input from the standard input stream in the following manner? I want the user to be able to input any number of characters, even 50,000 on the terminal before pressing enter. The number of input characters isn't fixed at the start. I don't want to store the input string, I just want to keep a count of how many characters are entered

Use a istream_iterator

Could you elaborate please…

istream_iteratot<char> inp(cin), end; unsigned count = 0; while(inp != end){ *inp++; ++count; } //count is the number of characters entered. If you dont want to consider the enter key then break out of the while loop if the user entered '\n'

//Write a program to input a character display the entered character is a vowel or not . #include <stdio.h> #include <stdlib.h> int main() { char c; printf("Enter a character \n"); scanf("%c", c); switch(c) { case 'a': printf(" %c is a vowel", c);break; case 'e': printf(" %c is a vowel", c);break; case 'o': printf(" %c is a vowel", c);break; case 'u': printf(" %c is a vowel", c);break; case 'i': printf(" %c is a vowel", c);break; default : printf(" %c is not a vowel", c); } }

pastecode.io/s/r02i1175 So I have this recursive function that prints values from the given number till 1, decrementing by 1 each time. Is there any way I can make the function return a vector consisting of the values instead of printing them? I'm trying to avoid global variables.

//Write a program to input a character display the entered character is a vowel or not . #include <stdio.h> #include <stdlib.h> int main() { char c; printf("Enter a character \n"); scanf("%c", c); switch(c) { case 'a': printf(" %c is a vowel", c);break; case 'e': printf(" %c is a vowel", c);break; case 'o': printf(" %c is a vowel", c);break; case 'u': printf(" %c is a vowel", c);break; case 'i': printf(" %c is a vowel", c);break; default : printf(" %c is not a vowel", c); } }

istream_iteratot<char> inp(cin), end; unsigned count = 0; while(inp != end){ *inp++; ++count; } //count is the number of characters entered. If you dont want to consider the enter key then break out of the while loop if the user entered '\n'

scanf("%c", &c); //you forgot the &

So I was thinking… this is such a fundamental problem so isn't there some more simplistic solution to this using only cin and while loops or maybe getchar()?

Yes you could do that albeit with some more lines of code.

Oh could you tell how? The reason is that I wanna solve this problem with the most basic tools, avoiding use of iterators or STL functions if possible

Dont use recursion. Use a while loop or for loop instead. Just create a vector in your func and push back the values you need. When you are done return the vector.

The actual code is more complex and I have to use recursion. I was thinking of static variable but there's no way to clear the vector for further calls of the function.

Pass in a vector by reference then.

Just use getchar() till you read EOF or '\n' and break out of the loop and print the number of characters encountered so far.

Now here's the interesting part… I tried this and it surprisingly runs into an infinite loop. EOF is out of question since I'm reading from terminal from standard input stream. Now when I write a loop as follows: char c; while(c != '\n') { c = getchar(); len++; } This goes into an infinite loop. It will take your input char stream but then when you press enter, it doesn't do anything. You keep pressing enter and nothing happens. Dunno why it happens 🤔

#include <stdio.h> int main(void) { int count = 0; while(getchar() != '\n') { ++count; } printf("%d\n", count); return 0; } This works fine on my system.

Now that the doubt is cleared, just for conceptual clarity what exactly is the difference in way that cin and getchar() work for my question? If you replaced the while loop condition with while(cin >> c) an infinite loop follows so there's some fundamental difference in the way that cin and getchar() are operating… anyone knows how?

while(cin>>c) tests the status of cin. If cin is in bad state, failed state or EOF state then this loop will terminate. It wont terminate as long as a valid input is read and that includes enter key presses. The while(getchar() != '\n') checks specifically that the key pressed is not the enter key. So you could do the same with cin as while((cin>>c) && c != '\n')

https://pastebin.com/9PjW5RBD It is returning null LinkedList, why so?

And why are you even using a vector? Doesnt it defeat the purpose of using a linked list in the first place? The sorted list can be created in place without using the vector by instead just manipulating the next pointers.

Actually without vector I tried but the same null head was being returned thats why I came to use it

Head is null because you are setting it to nullptr yourself.

What is the mechanism behind the rand() and srand() functions??

You want to know how pseudo random number generators work?

Yes please!

Well there are many ways you can generate them. The simplest way would be a linear congruential generator. You start with some number say a seed. You could generate the first number by substituting seed for x in (a*x+b) mod m where a,b and m are decided by the generator. Typically m is a very large prime number and a and b are less than m. The next number is generated by substituting the previous generated number for x in the above equation. That is why when you start with the same seed, you get the same sequence of random numbers. This is the simplest RNG and there are much better PRNGs in use. rand() doesnt use a Linear Congruential Generator btw.

Overstood, now which is better either to use the built in functions or to define my own?

I think. If you initialize the array while declaring it, like: int tab[siz]= {11, 22, 33}; This will produce some error.

wtf? error: cannot initialize return object of type 'VertexEngine::Triple<const char *, unsigned int, Diligent::ITexture *> *' with an lvalue of type 'VertexEngine::Triple<const char *, unsigned long, Diligent::ITexture *> *'