Zadana je 2D binarna matrica od N redovi i M stupci. Zadatak je provjeriti je li matrica vodoravno simetrična okomito simetrična ili oboje. Za matricu se kaže da je vodoravno simetrična ako je prvi redak isti kao zadnji redak, drugi redak je isti kao predzadnji red i tako dalje. Za matricu se kaže da je vertikalno simetrična ako je prvi stupac isti kao zadnji stupac, drugi stupac je isti kao predzadnji stupac i tako dalje.
Ispis ' VERTIKALNO 'ako je matrica vertikalno simetrična' VODORAVNO 'ako je matrica okomito simetrična' OBA ' ako je matrica vertikalna i horizontalna simetrična i ' NE ' ako nije simetričan.
Primjeri:
javascript datum
Ulazni: N = 3 M = 3
0 1 0
0 0 0
0 1 0
Izlaz: Oba
Obrazloženje: Prvi i treći red su isti, a drugi red je također u sredini. Dakle, horizontalna simetrija. Slično tome, prvi i treći stupac su isti, a drugi stupac je u sredini, tako da je okomito simetričan.Ulazni: N = 3 M = 3
0 0 1
1 1 0
0 0 1
Izlaz: Oba
Pristup: Ideja je koristiti pokazivače koji označavaju dva retka (ili stupca) i usporediti svaku ćeliju oba istaknuta retka (ili stupca).
- Za horizontalnu simetriju inicijalizirajte jedan pokazivač i = 0 i drugi pokazivač j = N - 1.
- Sada usporedite svaki element i-tog retka i j-tog retka. Povećajte i za 1 i smanjite j za 1 u svakom ciklusu petlje.
- Ako se pronađe barem jedan element koji nije identičan, označite matricu kao horizontalno simetričnu.
- Slično za okomitu simetriju inicijalizirajte jedan pokazivač i = 0 i drugi pokazivač j = M - 1.
- Sada usporedite svaki element i-tog stupca i j-tog stupca. Povećajte i za 1 i smanjite j za 1 u svakom ciklusu petlje.
- Ako se pronađe barem jedan element koji nije identičan, označite matricu da nije vertikalno simetrična.
Ispod je implementacija gore navedene ideje:
C++// C++ program to find if a matrix is symmetric. #include
// Java program to find if // a matrix is symmetric. import java.io.*; public class GFG { static void checkHV(int[][] arr int N int M) { // Initializing as both horizontal // and vertical symmetric. boolean horizontal = true; boolean vertical = true; // Checking for Horizontal Symmetry. // We compare first row with last // row second row with second // last row and so on. for (int i = 0 k = N - 1; i < N / 2; i++ k--) { // Checking each cell of a column. for (int j = 0; j < M; j++) { // check if every cell is identical if (arr[i][j] != arr[k][j]) { horizontal = false; break; } } } // Checking for Vertical Symmetry. We compare // first column with last column second column // with second last column and so on. for (int j = 0 k = M - 1; j < M / 2; j++ k--) { // Checking each cell of a row. for (int i = 0; i < N; i++) { // check if every cell is identical if (arr[i][j] != arr[i][k]) { horizontal = false; break; } } } if (!horizontal && !vertical) System.out.println('NO'); else if (horizontal && !vertical) System.out.println('HORIZONTAL'); else if (vertical && !horizontal) System.out.println('VERTICAL'); else System.out.println('BOTH'); } // Driver Code static public void main(String[] args) { int[][] mat = { { 1 0 1 } { 0 0 0 } { 1 0 1 } }; checkHV(mat 3 3); } } // This code is contributed by vt_m.
# Python3 program to find if a matrix is symmetric. MAX = 1000 def checkHV(arr N M): # Initializing as both horizontal and vertical # symmetric. horizontal = True vertical = True # Checking for Horizontal Symmetry. We compare # first row with last row second row with second # last row and so on. i = 0 k = N - 1 while(i < N // 2): # Checking each cell of a column. for j in range(M): # check if every cell is identical if (arr[i][j] != arr[k][j]): horizontal = False break i += 1 k -= 1 # Checking for Vertical Symmetry. We compare # first column with last column second column # with second last column and so on. i = 0 k = M - 1 while(j < M // 2): # Checking each cell of a row. for i in range(N): # check if every cell is identical if (arr[i][j] != arr[i][k]): vertical = False break j += 1 k -= 1 if (not horizontal and not vertical): print('NO') elif (horizontal and not vertical): print('HORIZONTAL') elif (vertical and not horizontal): print('VERTICAL') else: print('BOTH') # Driver code mat = [[1 0 1] [0 0 0] [1 0 1]] checkHV(mat 3 3) # This code is contributed by shubhamsingh10
// C# program to find if // a matrix is symmetric. using System; public class GFG { static void checkHV(int[ ] arr int N int M) { // Initializing as both horizontal // and vertical symmetric. bool horizontal = true; bool vertical = true; // Checking for Horizontal Symmetry. // We compare first row with last // row second row with second // last row and so on. for (int j = 0 k = N - 1; j < N / 2; j++ k--) { // Checking each cell of a column. for (int i = 0; i < M; i++) { // check if every cell is identical if (arr[i j] != arr[i k]) { horizontal = false; break; } } } // Checking for Vertical Symmetry. We compare // first column with last column second column // with second last column and so on. for (int i = 0 k = M - 1; i < M / 2; i++ k--) { // Checking each cell of a row. for (int j = 0; j < N; j++) { // check if every cell is identical if (arr[i j] != arr[k j]) { horizontal = false; break; } } } if (!horizontal && !vertical) Console.WriteLine('NO'); else if (horizontal && !vertical) Console.WriteLine('HORIZONTAL'); else if (vertical && !horizontal) Console.WriteLine('VERTICAL'); else Console.WriteLine('BOTH'); } // Driver Code static public void Main() { int[ ] mat = { { 1 0 1 } { 0 0 0 } { 1 0 1 } }; checkHV(mat 3 3); } } // This code is contributed by vt_m.
// PHP program to find if // a matrix is symmetric. function checkHV($arr $N $M) { // Initializing as both horizontal // and vertical symmetric. $horizontal = true; $vertical = true; // Checking for Horizontal Symmetry. // We compare first row with last row // second row with second last row // and so on. for ($i = 0 $k = $N - 1; $i < $N / 2; $i++ $k--) { // Checking each cell of a column. for ($j = 0; $j < $M; $j++) { // check if every cell is identical if ($arr[$i][$j] != $arr[$k][$j]) { $horizontal = false; break; } } } // Checking for Vertical Symmetry. // We compare first column with // last column second column with // second last column and so on. for ($j = 0 $k = $M - 1; $j < $M / 2; $j++ $k--) { // Checking each cell of a row. for ($i = 0; $i < $N; $i++) { // check if every cell is identical if ($arr[$i][$j] != $arr[$i][$k]) { $horizontal = false; break; } } } if (!$horizontal && !$vertical) echo 'NOn'; else if ($horizontal && !$vertical) cout << 'HORIZONTALn'; else if ($vertical && !$horizontal) echo 'VERTICALn'; else echo 'BOTHn'; } // Driver Code $mat = array(array (1 0 1) array (0 0 0) array (1 0 1)); checkHV($mat 3 3); // This code is contributed by nitin mittal. ?> <script> // Javascript program to find if // a matrix is symmetric. function checkHV(arr N M) { // Initializing as both horizontal // and vertical symmetric. let horizontal = true; let vertical = true; // Checking for Horizontal Symmetry. // We compare first row with last // row second row with second // last row and so on. for (let i = 0 k = N - 1; i < parseInt(N / 2 10); i++ k--) { // Checking each cell of a column. for (let j = 0; j < M; j++) { // check if every cell is identical if (arr[i][j] != arr[k][j]) { horizontal = false; break; } } } // Checking for Vertical Symmetry. We compare // first column with last column second column // with second last column and so on. for (let j = 0 k = M - 1; j < parseInt(M / 2 10); j++ k--) { // Checking each cell of a row. for (let i = 0; i < N; i++) { // check if every cell is identical if (arr[i][j] != arr[i][k]) { horizontal = false; break; } } } if (!horizontal && !vertical) document.write('NO'); else if (horizontal && !vertical) document.write('HORIZONTAL'); else if (vertical && !horizontal) document.write('VERTICAL'); else document.write('BOTH'); } let mat = [ [ 1 0 1 ] [ 0 0 0 ] [ 1 0 1 ] ]; checkHV(mat 3 3); </script>
Izlaz
BOTH
Vremenska složenost: O(N*M).
Pomoćni prostor: O(1)