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POAllocation - pointer-to-pointer
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  1. POAllocation - pointer-to-pointer
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    copied!<p>I would like to ask for help with allocation .... I got this homework to school...I have to write program which will load one G matrix and second G matrix and will search second G matrix for number of presences of the first G matrix....But, when I try to run my program I got Segmentation fault message... Thanks in advance. Example how the program is supposed to work....</p> <p>...</p> <p>Enter number of lines of wanted g matrix: 3 Enter the wanted g matrix:<br> 121212<br> 212121<br> 121212<br> G matrix to be searched:<br> 12121212121212<br> 21212121212121<br> 12121212123212<br> 21212121212121<br> 12121212121212<br> G matrix found 8 times. </p> <p>...</p> <p>this is my code: </p> <pre><code>#include &lt;stdio.h&gt; #include &lt;stdlib.h&gt; #include &lt;string.h&gt; char * get_line(void) // get line { char * string; if((string = (char *)malloc(100 * sizeof(char))) == NULL) { printf("Nedostatek pameti.\n"); // not enough memory exit(1); } int i = 0; while((string[i] = fgetc(stdin)) != '\n') { i++; if((i % 100) == 0) { if((string = (char *)realloc(string, 100 * ( i - 1 ) * sizeof(char))) == NULL) { printf("Nedostatek pameti.\n"); // not enough memory exit(1); } } } return ( string ); } char ** get_wanted_g_matrix(int pocetradek /*number of lines*/) // get wanted g matrix { char ** string; printf("Zadejte hledanou matici:\n"); int i = 0; if(( * string = (char ** )malloc(100 * sizeof(char *))) == NULL) { printf("Nedostatek pameti.\n"); // not enough memory exit(1); } while(i &lt;= (pocetradek - 1)) { string[i] = get_line(); if((i &gt; 1) &amp;&amp; (*string[i-1] != strlen(*string[i]))) { printf("Nespravny vstup.\n"); // not enough memory exit(1); } printf("%s", string[i]); i++; if((i % 100) == 0) { if((* string = (char **)realloc(* string, 100 * ( i - 1 ) * sizeof(char *))) == NULL) { printf("Nedostatek pameti.\n"); // not enough memory exit(1); } } } return (string); } int get_number_of_lines(void) // get number of lines { int number_of_lines; printf("Zadejte pocet radek hledane matice:\n"); // enter the number of lines of wanted g matrix if(scanf("%d", &amp;number_of_lines) != 1) { printf("Nespravny vstup.\n"); // Error exit(1); } return ( number_of_lines ); } char ** get_searched_g_matrix(void) // get wanted g matrix { char ** string; printf("Matice, ktera bude prohledana:\n"); // G matrix to be searched int i = 0; if(( * string = (char ** )malloc(100 * sizeof(char *))) == NULL) { printf("Nedostatek pameti.\n"); // not enough memory exit(1); } while(!feof(stdin)) { string[i] = get_line(); if((i &gt; 1) &amp;&amp; (*string[i-1] != strlen(*string[i]))) { printf("Nespravny vstup.\n"); // error exit(1); } printf("%s", string[i]); i++; if((i % 100) == 0) { if((* string = (char **)realloc(* string, 100 * ( i - 1 ) * sizeof(char *))) == NULL) { printf("Nedostatek pameti.\n"); // not enough memory exit(1); } } } if(feof(stdin)) { return string; } } int search( char ** string1, char ** string2 ) // search { int string1width = strlen(*string1[0]); int string2width = strlen(*string2[0]); int string2height = strlen(**string2); int number_of_lines = get_number_of_lines(); unsigned int g = 0, h = 0, i2, j2, l = 0, i = 0, j; while( i &lt;= (string2height - 2) ) { j = 0; while( j &lt;= string2width - 2 ) { g = 0; h = 0; if(string2[i][j] == string1[g][h]) { i2 = i; while((g &lt;= number_of_lines - 1) &amp;&amp; (i2 &lt;= string2height - 2)) { j2 = j; h = 1; while(((string2[i2][j2] == string1[g][h]) &amp;&amp; (j2 &lt;= string2height - 2)) &amp;&amp; (h &lt;= string1width - 2)) { j2++; h++; } if(h != string1width - 1) { break; } if(g == number_of_lines - 1) { l++; break; } i2++; g++; } } j++; } i++; } return ( l ); } int main(void) { char ** string1; char ** string2; int number_of_lines = get_number_of_lines(); string1 = get_wanted_g_matrix(number_of_lines); string2 = get_searched_g_matrix(); if(feof(stdin)) { printf("Matice nalezena %d krat.\n", search( ** string1, **string2 )); // G matrix found %d times. } return 0; } </code></pre>
 

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