Glede na n x n binarna matrika (elementi v matriki so lahko 1 ali 0), kjer se vsaka vrstica in stolpec matrice razvrsti v število povečanih številk 0, ki je prisotna v njej.
Primeri:
Vnos:
[0 0 0 0 1]
[0 0 0 1 1]
[0 1 1 1 1]
[1 1 1 1 1]
[1 1 1 1 1]
Izhod: 8
Vnos:
[0 0]
[0 0]
Izhod: 4
Vnos:
[1 1 1 1]
[1 1 1 1]
[1 1 1 1]
[1 1 1 1]
Izhod:
Ideja je zelo preprosta. Začnemo od spodnjega levega kota matrice in ponovimo pod koraki, dokler ne najdemo zgornjega ali desnega roba matrice.
- Indeks vrst Decrement, dokler ne najdemo 0.
- Dodajte število 0 v trenutnem stolpcu, tj. Indeks trenutne vrstice + 1 v rezultat in premaknite desno na naslednji stolpec (indeks povečevanja col za 1).
Zgornja logika bo delovala, saj je matrica razvrščena v vrsto in v stolpcu. Logika bo delovala tudi za katero koli matrico, ki vsebuje ne-negativna cela števila.
Spodaj je izvedba zgornje ideje:
vzorec načrtovanja tovarniške metodeC++
#include #include using namespace std; // Function to count number of 0s in the given // row-wise and column-wise sorted binary matrix. int countZeroes(const vector<vector<int>>& mat) { int n = mat.size(); // start from the bottom-left corner int row = n - 1 col = 0; int count = 0; while (col < n) { // move up until you find a 0 while (row >= 0 && mat[row][col]) { row--; } // add the number of 0s in the current // column to the result count += (row + 1); // move to the next column col++; } return count; } int main() { vector<vector<int>> mat = { { 0 0 0 0 1 } { 0 0 0 1 1 } { 0 1 1 1 1 } { 1 1 1 1 1 } { 1 1 1 1 1 } }; cout << countZeroes(mat); return 0; }
C // C program to count number of 0s in the given // row-wise and column-wise sorted binary matrix. #include // define size of square matrix #define N 5 // Function to count number of 0s in the given // row-wise and column-wise sorted binary matrix. int countZeroes(int mat[N][N]) { // start from bottom-left corner of the matrix int row = N - 1 col = 0; // stores number of zeroes in the matrix int count = 0; while (col < N) { // move up until you find a 0 while (mat[row][col]) // if zero is not found in current column // we are done if (--row < 0) return count; // add 0s present in current column to result count += (row + 1); // move right to next column col++; } return count; } // Driver Program to test above functions int main() { int mat[N][N] = { { 0 0 0 0 1 } { 0 0 0 1 1 } { 0 1 1 1 1 } { 1 1 1 1 1 } { 1 1 1 1 1 } }; printf('%d'countZeroes(mat)); return 0; }
Java import java.util.Arrays; public class GfG { // Function to count number of 0s in the given // row-wise and column-wise sorted binary matrix. public static int countZeroes(int[][] mat) { int n = mat.length; // start from the bottom-left corner int row = n - 1 col = 0; int count = 0; while (col < n) { // move up until you find a 0 while (row >= 0 && mat[row][col] == 1) { row--; } // add the number of 0s in the current // column to the result count += (row + 1); // move to the next column col++; } return count; } public static void main(String[] args) { int[][] mat = { { 0 0 0 0 1 } { 0 0 0 1 1 } { 0 1 1 1 1 } { 1 1 1 1 1 } { 1 1 1 1 1 } }; System.out.println(countZeroes(mat)); } }
Python # Function to count number of 0s in the given # row-wise and column-wise sorted binary matrix. def count_zeroes(mat): n = len(mat) # start from the bottom-left corner row = n - 1 col = 0 count = 0 while col < n: # move up until you find a 0 while row >= 0 and mat[row][col]: row -= 1 # add the number of 0s in the current # column to the result count += (row + 1) # move to the next column col += 1 return count if __name__ == '__main__': mat = [ [0 0 0 0 1] [0 0 0 1 1] [0 1 1 1 1] [1 1 1 1 1] [1 1 1 1 1] ] print(count_zeroes(mat))
C# // Function to count number of 0s in the given // row-wise and column-wise sorted binary matrix. using System; using System.Collections.Generic; class Program { static int CountZeroes(int[] mat) { int n = mat.GetLength(0); // start from the bottom-left corner int row = n - 1 col = 0; int count = 0; while (col < n) { // move up until you find a 0 while (row >= 0 && mat[row col] == 1) { row--; } // add the number of 0s in the current // column to the result count += (row + 1); // move to the next column col++; } return count; } static void Main() { int[] mat = { { 0 0 0 0 1 } { 0 0 0 1 1 } { 0 1 1 1 1 } { 1 1 1 1 1 } { 1 1 1 1 1 } }; Console.WriteLine(CountZeroes(mat)); } }
JavaScript // Function to count number of 0s in the given // row-wise and column-wise sorted binary matrix. function countZeroes(mat) { const n = mat.length; // start from the bottom-left corner let row = n - 1 col = 0; let count = 0; while (col < n) { // move up until you find a 0 while (row >= 0 && mat[row][col]) { row--; } // add the number of 0s in the current // column to the result count += (row + 1); // move to the next column col++; } return count; } const mat = [ [0 0 0 0 1] [0 0 0 1 1] [0 1 1 1 1] [1 1 1 1 1] [1 1 1 1 1] ]; console.log(countZeroes(mat));
Izhod
8
Časovna zapletenost zgornje raztopine je o (n), saj raztopina sledi eni poti od spodaj levega vogala do zgornjega ali desnega roba matrice.
Pomožni prostor Uporablja program O (1). Ker ni bil odvzet dodatni prostor.