How to collect specific values from file and rewriting them to new file?-CodePudding

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#define LINE_SIZE 100

struct products{
char uAd[5];
int uID;
int uSat;
int uAl;
int uStk;
};

void collectTheStk(struct products *p);

int main(){

    FILE *f = fopen("file.txt","r");
    if(f==NULL){
        perror("file.txt");
        exit(1);
    }
    struct products U[10];
    size_t i; 

//the total line inside of the file is 10 so going through the end
    for (i = 0; i < 10; i   ) {
        char buf[LINE_SIZE];
        if (fgets(buf, sizeof(buf), f) == NULL) {
            break;
        }
        sscanf(buf, "%d %4s %d %d %d", &U[i].uID, 
        U[i].uAd, &U[i].uSat, &U[i].uAl, &U[i].uStk);
    }
    fclose(f);

    collectTheStk(U);

    return 0;
}

void collectTheStk(struct products *p){
    FILE *fy = fopen("newfile.txt","w");
    struct products newstk[10];
    for(int i=0;i<10;i  ){
        for(int j=0;j<10;j  ){
            if(i==j) continue;
            if((strcmp(p[i].uAd,p[j].uAd))==0){

//here i am taking the sum of stck number(and this is the point where i am struggling)
                newstk[i].uStk = p[i].uStk   p[j].uStk;
            }
        }
    }
    
    for(int n=0;n<10;n  ){
        fprintf(fy, "%d %s %d %d %d\n",p[n].uID, p[n].uAd, p[n].uSat, p[n].uAl, newstk[n].uStk);
    }
    fclose(fy);
    
    printf("\nProccess is done check your new file\n");
    
}

This is inside of the file.

1 A    20  15  5
2 B    50  30  10
3 CD   60  40  2
7 O    77  35  20
4 EFG  3   1   100
1 A    20  15  25
5 HJ   150 100 8
6 KLMN 5   1   23
7 O    77  35  12
7 O    77  35  40

Inside the file the last column is the uStk(stock number). And the letters are uAd(name of the products). The problem is the letters A and O are repeating on different lines with different stock numbers. So what i want is after reading the file getting the sum of stock numbers and write them in the new file.

I was expecting to get the following new file.

1 A    20  15  30
2 B    50  30  10
3 CD   60  40  2
4 EFG  3   1   100
5 HJ   150 100 8
6 KLMN 5   1   23
7 O    77  35  72

This is the file what i am getting right now.

1 A 20 15 1968936544
2 B 50 30 6421668
3 CD 60 40 71
7 O 77 35 1345228322
4 EFG 3 1 14747728
1 A 20 15 -357094208
5 HJ 150 100 6421736
6 KLMN 5 1 6421824
7 O 77 35 -1604510652
7 O 77 35 -882665882

CodePudding user response：

newstk[i].uStk = newstk[i].uStk newstk[j].uStk; is bad as newstk[j].uStk never initialized nor assigned.

Zero out newstk[10] with:

struct products newstk[10] = { { 0 } };

Likewise for struct products U[10];.

struct products U[10] = { { 0 } };