#include #include #include #include // demo right shift dinamic array with grow // This is the style shift the array // to the right selector memory block #define RIGHT_SHIFT_MEMBLOCK // otherwise the style shift the array // to the right one element at a time typedef struct { int f1; char f2[27 + 1]; } item_t ; bool array_shift_right( item_t** pitem_arr, int* pn, int istep_grow ){ bool bShiftRes = false; if(istep_grow<1)return bShiftRes; int n_new = *pn + istep_grow; item_t* item_arr_rlct = (item_t*)realloc( *pitem_arr, (size_t)( n_new * sizeof(item_t) ) ); if( !item_arr_rlct ) { printf("error realloc array " " to size %i from size %i.", n_new , *pn); } else { *pitem_arr = item_arr_rlct; #ifdef RIGHT_SHIFT_MEMBLOCK //move memory block memmove( (*pitem_arr + istep_grow), (*pitem_arr), sizeof(item_t)* (*pn) ); #else //one element at a time for (int i = *pn - 1; i >= 0; i--) memcpy( (*pitem_arr + i + istep_grow), (*pitem_arr + i), sizeof(item_t) ); #endif //clear moved items memset(*pitem_arr, 0, sizeof(item_t)*istep_grow ); *pn = n_new; //Shift complited bShiftRes = true; }; return bShiftRes; } int main() { // Shift Dinamic array // create array int n = 99;// n in 1..99 item_t* item_arr = (item_t*)calloc( n, sizeof(item_t) ); // Fill logic: // we fill the array with values - in the // field f1 the number of the element when // filling, in the string of the field f2 we // enter the data as follows: the first // three characters are the number of the // element and arrow, and the next // characters to the end of the buffer // are the contents of the field f2 of // the previous element. item_t* item_arr_iter = item_arr; for (int i = 0 ; i < n; i++) { item_arr_iter->f1 = i+1; memset( item_arr_iter->f2, 0, sizeof( item_arr_iter->f2 ) ); if(i){ memcpy( (item_arr_iter->f2) + 3, ( (item_arr_iter - 1)->f2), ( (i+1)*3 < sizeof( item_arr_iter->f2 ) ? i*3 : ( sizeof( item_arr_iter->f2 ) - 1 - 3 ) ) ); }; item_arr_iter->f2[0]= ( i/10 ) + '0'; item_arr_iter->f2[1]= ( i%10 ) + '0'; item_arr_iter->f2[2]= '>'; if( i!=n-1 )item_arr_iter++; }; //Show array items printf("\n Array items: \n"); item_arr_iter = item_arr; for (int i = 0 ; i < n; i++) { printf(" {f1:%i, f2:\"%s\"}\n", item_arr_iter->f1, item_arr_iter->f2 ); if( i!=n-1 )item_arr_iter++; }; //.... //... some your code array_shift_right(&item_arr, &n, 4); printf("\n Array items after shift right 4: \n"); item_arr_iter = item_arr; for (int i = 0 ; i < n; i++) { printf(" {f1:%i, f2:\"%s\"}\n", item_arr_iter->f1, item_arr_iter->f2 ); if( i!=n-1 )item_arr_iter++; }; array_shift_right(&item_arr, &n, 5); printf("\n Array items after shift right 5: \n"); item_arr_iter = item_arr; for (int i = 0 ; i < n; i++) { printf(" {f1:%i, f2:\"%s\"}\n", item_arr_iter->f1, item_arr_iter->f2 ); if( i!=n-1 )item_arr_iter++; }; free( item_arr ); return 0; }

Demo right shift dinamic array with grow