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POShuffle array (seg fault)
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copied!<p>So I am supposed to create a function that accomplishes: Purpose: program to shuffle the lines of a text file</p> <ul> <li>Read the file into an array</li> <li>Count lines and maximum length</li> <li>Compute maximum width for array</li> <li>Get file pointer to the beginning</li> <li>Reserve memory for a dynamic array of strings</li> <li>Read a line and store in allocated memory</li> <li>Turn the \n into \0</li> <li>Print lines from array (test)</li> <li>Shuffle array</li> <li>Print lines from array (test)</li> <li>Free memory and close file</li> </ul> <p>(just to give some background)</p> <p>However, when I go to print the shuffled array, I get segmentation faults. Occasionally, it prints one or two of the strings, but sometimes It just says "Shuffled Array" and then I get a segmentation fault. Any ideas?</p> <pre><code>#include <stdio.h> #include <stdlib.h> #include <string.h> #include <time.h> // Accepts: command line input // Returns: 0 if no error int main(int argc, char *argv[] ){ int x = 0, i, lineCount = 0, maxLen = 0; char line[500], temp; FILE *file = fopen( argv[1], "r" ); // check if file exists if (file == NULL){ printf("Cannot open file\n"); return 1; } // Gets lines, max length of string while (fgets(line, sizeof(line), file) != NULL){ lineCount++; if (strlen(line) > maxLen) maxLen = strlen(line); } rewind(file); char *lineArray[lineCount]; while (fgets(line, sizeof(line), file) != NULL) { lineArray[x] = malloc(strlen(line)); if (lineArray[x] == NULL){ printf("A memory error occurred.\n"); return(1); } strcpy(lineArray[x], line); // change \n to \0 lineArray[x][strlen(lineArray[x])-1] = '\0'; x++; } printf("File %s has %d lines with maximum length of %d characters\n", argv[1], lineCount, maxLen); printf("Original Array\n"); for (x = 0; x < lineCount; x++) printf("%2d %s\n", x, lineArray[x]); // Shuffle array srand( (unsigned int) time(NULL)); for (x = lineCount - 1; x >= 0; x--){ i = (int) rand() % lineCount; temp = lineArray[x]; lineArray[x] = lineArray[i]; lineArray[i] = temp; } printf("\nShuffled Array\n"); for (x = 0; x < lineCount; x++) printf("%2d %s\n", x, lineArray[x]); // free allocated memory for (x = 0; x < lineCount; x++) free(lineArray[x]); free(lineArray); fclose(file); return 0; } </code></pre>

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