C++ :: How To Error Check If User Input Is Letters And Not Numbers
Jun 9, 2014
How do I error check if the user is inputting letters and not numbers? For example, if the user inputs "Lab.txt" I need to display an error message. If they input "Lab2part2.txt" then this is correct and what I want.
I've found a lot of information online on how to error check for numbers or a single letter (EX: 1,2,3, etc. or 'A' 'B' 'C') but nothing for actual WORDS or maybe I should refer to it as a string of characters?
Is there any way to do this? Because my program requires I ask the user to input the name of the file. But the way my code is currently set up is even when the user inputs the wrong file name it still opens the file. I want to prevent this from happening so my thought was to error check user input.
/*Program to determine company's weekly payroll*/
#include <iostream>
#include <string>
#include <fstream>
using namespace std;
void OpenTheFile() {
ifstream inputFile;
string filename;
char letter;
int number;
I am trying to write a program to get user's input but only accepts alphabetic characters, nothing else and I want it to ask the user to enter a valid word until they have finally entered a valid one. I have the following code for it but it does not work properly.
void CheckBound (char word1[], int SIZE1) { int i; int w1[SIZE4]= {0}; int found; for (i=0;i<strlen(word1);i++) {
#include <iostream> #include <limits> int getInt() { int x = 0; while(!(cin >> x))
[Code] ....
But this function prompts the user to only input integer values. I was thinking if I could maybe try tweaking with this one so that the user could only enter letters..no luck though. So how can I have the user input letters only?
So I am writing a program that counts the letters of 3 lines of input from the user. I am using a 3 x 80 character array as the "notepad". Upper and lower case characters are incremented on the same counter array.
Code:
/*Letters in a string*/ #include <stdio.h> #include <string.h> #include <ctype.h> void countAlphabet(char *); /*Character counting array*/ int alphabet[26] = {0};
I am trying to build a c++ that reads user input and arrange letters in ascending order.
for example, if the user input: Hello my name is Moe! the output will be: !aeeehillmmmnoos (ascending order)
my problem is that when i input hello my name is moe the output will be ehllo (not completing other letters) also when i change class size to 50, it outputs unknown weird letters.
This is my code:
#define CLASS_SIZE 10 #include <stdio.h> #include <iostream> void bubbleSortAWriteToB(const char a[], char b[]); using namespace std; int main(void){ int i;
I wonder how can I improve my validity check for user input? I only want them to key in certain range of digit.
Also for my validity check, when I key in character such as ABC, it lead to infinity loop
Here is my code : Code: /*Write a program that can calculate user's age by getting user input their birth date.*/
#include "stdafx.h" #include <iostream> #include <time.h> using namespace std; int main() { int yyyy, mm, dd; //year, month, day int i = 0; //for the sake of validity check
I'm trying to write a short program that takes the input from a user and trims any leading/trailing white space, and then checks how many words are in the string. Problem is, I'm only allowed to use stdio.h and stdlib.h. How can I accomplish this? Also, how would I check if any of the characters which were entered aren't either a number, letter, or '-'?
The purpose of this program is to unscramble the user's input. for example if the user entered 'ftooabll' the program would print 'football'. find the error that I am making....
Now, this only works for strings that are contained in the file wordlist. That being said, I would like this to repeat this search multiple times. Currently, the process is being repeated 7 times, but it only works on the first iteration. The code and sample input/output is below.
Sample input/output: (note: all data has been verified to be in the wordlist)
Enter string: 4132dcba abcd1234 Enter string: 4132dcba Enter string: 4132dcba Enter string: 4132dcba Enter string: 4132dcba Enter string: 4132dcba Enter string: 4132dcba
Now i got here a program that asks the user to input 2 numbers if the first inputed number is smaller than the second then show all even numbers from the range of the 1st inputed number till the 2nd inputed number, but if the first inputed number is greater than the second then display all odd numbers from the range of the 1st number till the 2nd.
now my question is how do i invert the odd numbers?(on the 2nd condition)
Code: #include<stdio.h> int main(void) { int i,a,b,x; printf("Enter two numbers"); printf(" First number:");
//Finding prime numbers #include <iostream> using namespace std;
[Code]....
/*The program currently prints all the prime numbers up to n (For example, if 7 is entered, it prints out: 1, 2, 3, 5, 7. What I want it to do, is print out the first 7 numbers; 1, 2, 3, 5, 7, 11, 13.
#include <iostream> #include <string> #include <limits> //for std: numeric limits #include <algorithm> //Function to get an integer from the user that is greater than or equal to zero.
int getPositiveIntFromUser(const std::string& prompt) { int retVal = -1;
[Code] ....
The first part works, but it doesn't calculate the GCD or LCM at all, it just crashes!
The program is supposed to read in a string from the user and then output the number of each vowel that the string has. My first function is initializing the vectors, and the one that I'm having trouble with is the function used to read the string from the user and save it.
// FUNCTION PROTOTYPES GO HERE: void init_vectors(vector<char> & vowels, vector<int> & frequencies); string read_text(const string & prompt);
[Code] ....
And I'm getting the error:
freq.cpp: In function ‘std::string read_text(const std::string&)’: freq.cpp:74: error: no matching function for call to ‘getline(std::istream&, const std::basic_string<char, std::char_traits<char>, std::allocator<char> >&)’
I'm not too sure if I can't use the function getline here or if there is something wrong with the function prototype itself but I'm pretty sure there isn't an error there as it was given to me.
I need validation on what the user inputs. Input should not be an alphabet, empty, and not negative number. This program is for finding the GCD and LCM of multiple numbers.
#include <stdio.h> void bubble_sort(int numbers[], int len) { int i, j; int swapped;
I'm suppose to write a program using (for loop) that asks the user to enter any amount of numbers, so that it can display the smallest and largest. My program successfully finds the largest, but it is always displaying 0 for the smallest, I think Im doing something wrong with the internalization but I dont know what to change it to.
This is what I have ....
#include <iostream> using namespace std; int main() { int amount; int count; int number = 0; int smallest = 0; int largest = 0; cout << "Enter total numbers to process: ";
I have to write a program where the user will input integer numbers. How many numbers they enter is unknown, therefor you should use a repetition structure for the input. When the user is done, they will enter -1 to exit.
Create a dynamic array if the size=2( the initial size must be 2) Repeat until user enters -1.
I have to do this without using vectors.
This is what i have, I cannot figure out what to put in main. I was thinking of a do-while?
Code: #include <iostream> using namespace std; void resize(int *[], int); int main() { int *listDyn; int size=2;
I am trying to code a program that takes in user inputted data about percentages and using it to later on calculate a final grade. 4 percents are inputted, for Assignments, Midterm1, Midterm2, and Finals. If the percents dont add up to 1 (i tell the user to enter the decimal value) I set up and if statement to catch it and end the program. Except that if i type in
So I have to make a program that allows the user to enter both positive and negative numbers and the program is suppose to calculate the sum of only the positive values while ignoring the negative values. Also it is to be a sentinel-controlled loop with a number ending the set of values.
I need to create A program That makes a 12x10 Array Grid Filled With Random Numbers From 0-99.
Then I need To Allow The User To Input A Number Between 0-99 And Then The program will then search through the array and count how many of the users number there is inside the array.
Code:
#include <iostream> using namespace std; int main() { int input; int number; int row=0; int col=0; int Array [12][10];
I have tried writing a code which takes two numbers from the user and calculates their square root then the roots are added up to return the sum. The program is coming out with loads of errors.
#include<iostream> #include<cmath> float main(){ using namespace std; float m1,m2,m3,m4,m5;
Code: #include<stdio.h> #include<string.h> #define a 9 #define b 9 #define c 3 int main() {
[Code] .....
In practice section there was a challenge to print up numbers in letters up to billion including negatives I didn't look at the solution and came up with this but it is getting difficult after this point....
