#include <stdio.h> #include <stdlib.h> #include <conio.h> #include <math.h> #include <locale.h> #include <iostream> int mass(float a[5][5], int *k) //функция преобразования массива { FILE *f1, *f2; int i, j = *k, n; float b[5][5]; printf("Введите степень\n"); scanf_s("%d", &n); for(i = 0; i < 5; i++) { for(j; j < 5; j++) { fscanf(f1, "%f", &a[i][j]); fclose(f1); b[i][j] = pow(a[i][j], n); printf("%9.0f ", b[i][j]); } printf("\n"); } return i; } void main() { setlocale(LC_ALL, "RUS"); int i, j, k = 0; float c[5][5]; FILE *f1, *f2; f1 = fopen("FILE1.dat", "r"); for(i = 0; i < 5; ++i) for(j = 0; j < 5; ++j) i = mass(c, &k); f2 = fopen("FILE2.dat", "w"); fclose(f2); }

The idea is this: the original data is read from one file and written to another. And there is no record. Here is a mistake:

Unhandled exception in "0x7c90100b" in "lab1.exe": 0xC0000005: Access violation when reading "0xcccccd00".

I can not understand why, what is the error.

    2 answers 2

    Pointers to f1 and f2 in the function body are defined locally.
    They are simply = NULL.
    You need to override the function int mass(float a[5][5],int*k,FILE*f1,FILE*f2) ,
    and call it i=mass(c,&k,f1,f2);

    • 0xcccccd00 is clearly not null. But the default value of variables in VS in debug mode is very similar. - Qwertiy ♦

    Unhandled exception in "0x7c90100b" in "lab1.exe": 0xC0000005: Access violation when reading "0xcccccd00".

    Most likely, in the line on which this error occurs, an uninitialized pointer is used.