i want to write a program which find the biggest prime factor of a number for example the biggest prime factor of six is three or the biggest prime factor of fifteen is five. What is my program bug
Code:
#include <stdio.h> // main functions
#include <math.h> // for sqrt function
int main()
{
int i, j, k, f; // F = Flag;
printf("Enter K
[Code]...
I am trying to find the largest prime factor of a number. But when I am trying to determine if a number is a prime number in the function:
int is_prime(int number), I am unable to exit the loop.
Here is the code:
#include<iostream>
using namespace std;
int is_prime(int number) //the problem is in this function {
int num = number;
int factor=0;
do{
num++;
for(int i=1;i<(num+1);i++){
[code].....
So when the program runs, it first divides 20 by 2, to get 10, then divides 10 by 2 to get 5. Since, // condition 1 is not met, it passes 2 to the function int is_prime(int number). The function is able to return 3, but cannot exit the loop when num is 4.
I think the problem lies in the function: int is_prime(int number).
I'm having this issue where my else if statements are not working. My program only works correctly when I go into my if statement and change the first part of my array to the specific row I am trying to find ex [0][i] to [1][i].
int getMonthMax(int scores[][COLS],int month){
int highestN=0,i, j;
for (i=0;i<ROWS-1;i++){
if(scores[0][i]>highestN){
highestN=scores[0][i];
[Code] .....
I need codes for a program in C or C++ that will show the real factor (the smallest one, without the number 1) when an integer is given as input.
When the program is started, it will ask to enter a number and press enter. After entering a number, it will first check if it is a prime number or not. If prime, it will notice that it is a prime number, otherwise, it will print the smallest real factor of the given integer.
For example, if 12 is entered, it will print, the smallest real factor for this number is: 2
If 27 is entered, it will print, the smallest real factor for this number is: 3
...and so on
While finding the primes , I do not know how to make it into one array so that...
View 7 Replies View Relatedfind the prime factors of the number input by the user. This time, we are going to have the user input a number, and the program will find all prime numbers from 2 to that number and prime factors of the number input by the user
#include <iostream>
#include <cmath>
using namespace std;
[Code]......
I am trying to write code to find all the prime numbers before a user entered number. I started with a working program and when I tried to create a function, it got all messed up.
Code:
#include <stdio.h>
int is_prime( int num );
int get_positive_integer(void);
int main( ) {
int upper; /* upper limit to check */
int num; /* current number to check */
int isprime;
/* used to flag if number is prime or not */
[Code]...
It says the error is on line 23
Here is the draft of code that i designed. My task is here to create the matrix, allocate the dynamic memory for it, and to find the biggest sum of the column elements that is located over main diagonal. So main points is correct memory allocation, and the sorting to the biggest sum of column higher than diagonal.
View 14 Replies View RelatedHow to find the biggest column of the matrix (higher of main diagonal) Here is the draft of code that i desighned/ Of cause it has a several mistake. My task is here to create the matrix, allocate the dynamic memory for it, and to find the biggest sum of the column elements that is located over main diagonal. So main points is correct memory allocation, and the sorting to the biggest sum of column higher than diagonal.
#include<iostream>
#include<conio.h>
#include<time.h>
using namespace std;
[Code]....
I'm supposed to find the biggest number (largest value), in any given array A with n numbers. (no floats)
My thoughts here are, check if A[0] > A[1]. if yes, check if A[0] > A[2]. If no, check if A[1] > A[2] etc.
I'm not sure how I can do this in code. I'm thinking if A[0] > A[1] is true, then set A[0] = A[k]. Kind of set it aside, and use that for the next if test. But I'm not sure how to do it.
This is my code so far.
Code:
int main(){
int A[7] = {12, 6, 9, 33, 2, 25, 53};
int i, k;
k = 0;
[Code]....
I'm aware of the flaws here, but this is the best I can do so far. How can I get the if test to use A[k] next, as A[k] will always be the biggest value?
Write a C-program that efficiently multiplies a number by a factor 2 to the power n. The number to multiply and n are variables, which get a value at the start of the program.
Clue: 1 shift to the left is the same as multiplying by 2. 2 shifts to the left are the same as multiplying by 4. 3 shifts to the left are the same as multiplying by 8
I have a program that gets prime numbers that doesn't work. It looks like it works for all prime numbers except odd non-prime ones. Here is the code:
Code:
#include <iostream>
using namespace std;
bool isPrime(int prime) {
while(true) {
int track = 0;
[Code] ...
I'm a new coder for C++, and I've recently learned java before starting this programming language. I'm attempting to find all prime numbers up to the number a user enters (i.e. User enters 10, System shows "1,2,3,5,7"),
#include <iostream>
#include <cstdlib>
using namespace std;
int main(int argc, char** argv) {
int num;
cout << "Enter a positive number." << endl;
[Code] ....
I've been looking at my forloop, and I can't seem to pinpoint the problem with it.
I need to write a program that will allow the user to enter a number "n" and the program tell you that the nth prime number is .....
EXAMPLE
user enters 55
printf("The 55th prime number is %i", variable");
I am attempting to write code that receives a number from the user and outputs the largest prime number underneath the user's number. There are no errors in my code, but no matter what number is imputed, the program says the largest prime number is 1. I cannot find where the issue is in the code. Here is the code I wrote:
#include <cstdlib>
#include <iostream>
#include <cmath>
using namespace std;
bool isPrime(int num);//function prototype
[Code] ....
I wrote some code for class to find prime numbers.The teacher says that I need to revise my code with the requirement below: use a bit array to store the prime number checking. The bit array will also be in the heap. Use the max value of an unsigned 32-bt integer (UINT_MAX) to be the maximum size of the prime number you want to check.
Code:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>
#include <getopt.h>
#include <ctype.h>
#include <stdint.h>
//function to set all non-primes to 0
void *zero_multiples(void *threadid);
[Code] .....
I am trying to create a program that lists all prime numbers within a range of two number. Why the below program isn't working?
#include <iostream>
using namespace std;
int main(){
int high_range;
int low_range;
int w;
[Code] .....
#include<iostream>
#include <cstdlib>
using namespace std;
[Code].....
i did a code that determine if the number is prime or not, and i have to do a one that finding the prime numbers between two variables .
the first code:
#include<iostream>
using namespace std;
int main(){
[Code].....
I have reduced it for lower numbers but for some reason with higher numbers when i get the program to out put all the primes they are in minuses!!!
I need a way to make this even faster, or maybe theres a better mathematical answer, I know that for numbers in their 1,000,000,000,000 have an average of 1 prime every 26.6 numbers (i think thats right there is 37,607,912,018 primes in the number 1,000,000,000,000) is there anyway i can utilize this??
#include <iostream>
using namespace std;
int main() {
int primeanswer = 1,p = 1;
for (int i=1;i<35; i++)
[Code] .....
I had to write a program to find all the primes between 1 and 100 using the sieve of Eratosthenes so I wrote this program :
#include <iostream>
#include <vector>
using namespace std;
// find all the primes number using Eratosthenes
int main() {
vector<bool> numbers(101);
[Code] .....
My problem is that if I try to modify the program to find all the primes between 1 and max (setting the size of the vector uqual to max) my program becomes slower and I would like to listen by other people some possible solution to don't use vector in this program, the author hasn't shown me yet how to delete a value from a vector so I just used this method to solve the problem.
As an assignment for school , I've to write a program to find the sum prime factors of a user input integer.
E.g. 20 = 2 x 2 x 5 , Sum = 2 + 2 + 5 = 9
E.g. 10 = 2 x 5 , Sum = 2 + 5 = 7
My method for finding the result is as follows :
- Divide the number by increasing values if int i , starting from i=2.
- Once I get a value of i that can divide the number without giving me a remainder , I add this value of i to int sum and divide the number by i.
- I will repeat this process until the user input value is equal to 1.
My code is as shown:
#include<stdio.h>
int primecheck(int n); // Function to check if i is prime
int primesum(int n); // Function to sum the values of i that are prime
int main(void) {
int n;
int sum;
printf("Enter a number (> 1): "); //Prompting and scanning user input ,n
scanf("%d",&n);
sum = primesum(n);
[Code] .....
But for some reason I keep getting an incorrect result, it's as if it is missing out the last factor for each case.
Eg. 20 = 2 x 2 x 5 , the result I get is 4 , which is 2+2
Eg. 40 = 2 x 2 x 2 x 5 , the result I get is 6 , which is 2+2+2;
I've looked through my code numerous times.
I made a program which finds the prime numbers from 0 to 100 million, and ran it on my laptop (core 2 duo, 1.83ghz, 2gb ram). It takes around 35 seconds for it to sieve all the non-prime numbers on my laptop.
I then ran the same program on a windows server, 2x 64 bit Intel Xeon Quad Core Processors @ 1.6 ghz, 6gb ram, and it takes the same amount of time, even when I set the priority to high and the affinity to all 8 cores, it seems to only use one core for the processing, is there any way to make it use all 8 cores at close to 100%?
#include <iostream>
using namespace std;
int main() {
//input output
[code]....
its supposed to tell whether the inputted number is prime or not
I have to create a program where I need to find the prime factors of a number and express it using exponents.
For example, for the number 1368 should output:
1368 = 2^3 * 3^2 * 19^1
This is my code:
void primeFact (int n){
int i;
int score = 0;
[Code].....
I am trying to factorize semi-prime numbers by using a brute force method and a square root method.The brute force method should start by multiplying all odd numbers between 1 and the semi-prime number. Meaning that 1 should multiply 3 then 5 then 7, etc. Then three should multiply 5 then 7 then 9 and so forth. The first number would never multiply a number equal to or less than itself.
bruteForce(int x){
f1 = 1;
f2 = f1 + 2;
while (f1 < x){
for (f2 = x; f2 <= x; f2-2){
[Code] ....
For my other algorithm, I want it to get the square root of the semi-prime and then start multiplying odd numbers around it. I made it so that the square root would have to be set to the next even number (in case it was a factor). If the product of the two odd numbers (a * b) is greater than the original semi-prime, I would multiply b by the next smaller number than a. Conversely, if the product of a and b is less than the original semi-prime, it will multiply a by the next odd number larger than b. This will repeat until the two correct factors of the original semi-prime are found.
Algorithm:
SquareRootFactorize(int x){
int N = x;
sqrtN = sqrt(N);
if (isOdd(sqrtN) == true)
sqrtN = sqrtN + 1;
f1 = sqrtN - 1;
f2 = sqrtN + 1;
[code].....