Question

Sales person Month6 Month7 Month8 Month9 Month10 Month11 Adam Ellen Eva Justin 2000 200 4000 125 3000 225 2500 110 3000 65 4000 85 2500 100 3000 315 4000 100 4500 300 3500 150 6000 350 3000 250 5000 650 6000 125 4000 200 4000 300 7000 500 8000 350 5000 650 5000 200 3000 125 4000 625 7000 225

how to use c language to read the date from a file called "figures.txt"? includ name and number,And how to declare a set of variables which are name of the salesperson, net income, discount.

Answer 1

Figures.txt :- (separate every word with a space ' ')

Sales Person Month6 Month7 Month8 Month9 Month10 Month11
================================================================
Adam 2000 200 3000 65 4000 100 5000 650 7000 500 3000 125
Ellen 4000 125 4520 65 9000 152 5600 458 8900 356 4850 139

Here is the C code :-

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
char * readline(FILE *fp, char *buffer)
{
    int ch;
    int i = 0;
    size_t buff_len = 0;

    buffer = malloc(buff_len + 1);
    if (!buffer) return NULL; 

    while ((ch = fgetc(fp)) != '\n' && ch != EOF)
    {
        buff_len++;
        void *tmp = realloc(buffer, buff_len + 1);
        if (tmp == NULL)
        {
            free(buffer);
            return NULL;
        }
        buffer = tmp;

        buffer[i] = (char) ch;
        i++;
    }
    buffer[i] = '\0';

    if (ch == EOF && (i == 0 || ferror(fp)))
    {
        free(buffer);
        return NULL;
    }
    return buffer;
}



int main()
{
    char *fileName = "figures.txt";
    FILE *file = fopen(fileName, "r");
    char *s;
    int length=0,i=0;
    char *salesPerson="";
    int netIncome=0;
    int discount=0;
    int t=0;
    while ((s = readline(file, 0)) != NULL)
    {
        if(i>=2){
            length=strlen(s);
            char * token = strtok(s, " ");
            t=0;
            salesPerson=token;
            while( token != NULL ) {
                token = strtok(NULL, " ");
                if(t%2!=0){
                    netIncome=netIncome+atoi(token);
                }
                else{
                    discount=discount+atoi(token);
                }
                t++;
            }
            printf("%s\t%d\t%d\n",salesPerson,netIncome,discount);
        }
        free(s);
        i++;
    }
    return 0;
}

Output :-

gcc HomeworkLib3.c
./a.exe   
Adam 1640 24000
Ellen 2935 60870