Member Avatar for jkamugisha 
             // c program to add 10 elements entered by the user
            #include <stdio.h>  
            int main ()
            {   
              int i;    
              float elements[10];       //declaring the array
              float sum = 0;

              for (i = 0; i < 10; ++i)
                {
                  printf ("Enter element %d: ", i + 1); //getting the elements from the user
                  scanf ("%f", &elements[i]);   //storing the elements
                  sum += elements[i];   //adding integers entered by the user to the sum variable

                }

              printf ("sum of above entered elements is : %.4f", sum);  //printing the sum to four decimal places
              return 0;
            }
Edited by jkamugisha
  • 2 Contributors
  • 4 Replies
  • 425 Views
  • 1 Day Discussion Span
  • Latest Post Latest Post by rproffitt

Dani AI

Generated

A reliable approach is to read each input line as a string (fgets) and parse it with strtod/strtof. That lets you: (1) accept signed/decimal/exponent formats, (2) detect non-numeric trailing characters, and (3) reprompt cleanly when the input is invalid. This avoids the common traps seen in the thread: using isdigit on a whole token (it only checks single digit characters) and mixing scanf with string buffers (which can leave input behind or use the wrong types). tried isdigit and a char buffer; asked for the expected behavior — the example below reads exactly 10 valid floats and sums them, reprompting on bad input.

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>

int main(void) {
    const int N = 10;
    char line[128];
    int got = 0;
    double sum = 0.0;

    while (got < N) {
        printf("Enter element %d: ", got + 1);
        if (!fgets(line, sizeof line, stdin)) break;

        /* skip leading whitespace */
        char *p = line;
        while (isspace((unsigned char)*p)) p++;
        if (*p == '\0' || *p == '\n') {
            printf("empty input, try again\n");
            continue;
        }

        errno = 0;
        char *end;
        double v = strtod(p, &end);
        if (end == p || errno == ERANGE) {
            printf("invalid or out-of-range number, try again\n");
            continue;
        }

        /* ensure only whitespace follows the number */
        while (isspace((unsigned char)*end)) end++;
        if (*end != '\0' && *end != '\n') {
            printf("unexpected characters after number, try again\n");
            continue;
        }

        sum += v;
        got++;
    }

    printf("sum of entered elements is : %.4f\n", sum);
    return 0;
}

Notes: use strtof if you want single-precision storage; check errno==ERANGE to catch range errors; prefer the fgets+strtod pattern whenever you need robust validation and clean error recovery.

Recommended Answers

All 4 Replies

Member Avatar for jkamugisha

kindly help because i have tried and tried but i could not get the exact output i wanted

Member Avatar for rproffitt

Line 12 seems to input floats. But your reply now writes you can not get the exact output you wanted but didn't share what happened versus what you wanted.

Member Avatar for jkamugisha 
     **   I tried to use *isdigit* but i could not get the the exact output i wanted **





         #include <stdio.h>
            #include<stdlib.h>
            #include<string.h>
            #include<time.h>
            #include<ctype.h>
            int main ()
            {   
              int i;    
              char elements[10];        //declaring the array
              float element;
              float sum = 0;

              for (i = 0; i < 10; ++i)
                {
                  printf ("Enter element %d: ", i + 1); //getting the elements from the user 
                  //fgets(elements[i], 10, stdin);
                  scanf ("%s", &(elements[i])); //storing the elements 

                  if (isdigit(elements[i]))
                 { 
                    element=atof(elements[i]);
                     sum += element;    //adding elements  entered by the user to the sum variable  
                 }
                else
                 {printf("invalid input()\n");
                     break;
                 }
                }

              printf ("sum of above entered elements is : %.4f", sum);  //printing the sum to four decimal places
              return 0;
            }
Edited by jkamugisha
Member Avatar for rproffitt

First you appear to have mark this solved.

Second, you mention "output" a second time yet you neglect to share what the output was and share what you wanted the output to be.

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.