Question

Problem 2 Sudoku is a logic-puzzle game played on a 9 x 9 grid, which is also sub-divided into 9 smaller grids of size 3x3 called bores. The goal of the game is to place the digits 1 - 9 in each column, row, and box such that no digit appears twice in any column, row, or box. You can read more about the rules of Sudoku here, please also use this source to determine how the boxes are seperated. Complete the C program sudoku.c by implementing the function check Sudoku which takes in a 9 x 9 2D-Array of ints that represents a Sudoku puzzle and returns true if it is in a "valid state" and false otherwise. For our purposes the Sudoku is considered in a valid state if no digit appears more than once in any column, row, or box. The Sudoku does not have to be fully solved for it to be in a valid state. That means some of the numbers in the Sudoku can be "left blank". Since the number 0 is not used in Sudoku puzzles we will use the integer 0 to represent a blank number. Since the number 0 is not actually part of our Sudoku but rather represents a blank number there can be as many O's as one likes in a column, row, or box and that does not mean the Sudoku is not in valid state.

Starting code:

#include <stdio.h>
#include <stdbool.h>
#include <assert.h>

bool checkSudoku(int sudoku[9][9])
{
    //code goes here
}

int main() {
    int sudoku[9][9] = {{7, 3, 5, 6, 1, 4, 8, 9, 2},
                        {8, 4, 2, 9, 7, 3, 5, 6, 1},
                        {9, 6, 1, 2, 8, 5, 3, 7, 4},
                        {2, 8, 6, 3, 4, 9, 1, 5, 7},
                        {4, 1, 3, 8, 5, 7, 9, 2, 6},
                        {5, 7, 9, 1, 2, 6, 4, 3, 8},
                        {1, 5, 7, 4, 9, 2, 6, 8, 3},
                        {6, 9, 4, 7, 3, 8, 2, 1, 5},
                        {3, 2, 8, 5, 6, 1, 7, 4, 9}};
    assert(checkSudoku(sudoku)==true);
    sudoku[0][0] = 0;
    assert(checkSudoku(sudoku)==true);
    sudoku[0][1] = 0;
    assert(checkSudoku(sudoku)==true);
    sudoku[0][0] = 8;
    assert(checkSudoku(sudoku)==false);
}

Answer 1

#include <stdio.h>
#include <stdbool.h>
#include <assert.h>

bool checkSudoku(int sudoku[9][9])
{
//check each row
for(int i = 0;i<9;i++){
int unq[10] ={0};
for(int j = 0; j<9;j++){
if(sudoku[i][j] ==0){
continue;
}
if(unq[sudoku[i][j]] != 0) return false;
else unq[sudoku[i][j]]++;
}
  
}
  
//check each column
for(int i = 0;i<9;i++){
int unq[10] ={0};
for(int j = 0; j<9;j++){
if(sudoku[j][i] ==0) continue;
  
if(unq[sudoku[j][i]] != 0) return false;
else unq[sudoku[j][i]]++;
}
  
}
  
//check each sub-box
  
int x = 0 , y = 0;
  
while(x<9 && y<9){
int unq[10] = {0};
for(int i = x;i<x+3;i++ )
for(int j = y;j<y+3;j++){
if(sudoku[i][j] ==0) continue;
  
if(unq[sudoku[i][j]] != 0) return false;
else unq[sudoku[i][j]]++;
}
  
x += 3;
if(x == 9 && y<6){
x = 0;
y +=3;
}
}
return true;
}

//square boxes checking

int main() {
int sudoku[9][9] = {{7, 3, 5, 6, 1, 4, 8, 9, 2},
{8, 4, 2, 9, 7, 3, 5, 6, 1},
{9, 6, 1, 2, 8, 5, 3, 7, 4},
{2, 8, 6, 3, 4, 9, 1, 5, 7},
{4, 1, 3, 8, 5, 7, 9, 2, 6},
{5, 7, 9, 1, 2, 6, 4, 3, 8},
{1, 5, 7, 4, 9, 2, 6, 8, 3},
{6, 9, 4, 7, 3, 8, 2, 1, 5},
{3, 2, 8, 5, 6, 1, 7, 4, 9}};
assert(checkSudoku(sudoku)==true);
sudoku[0][0] = 0;
assert(checkSudoku(sudoku)==true);
sudoku[0][1] = 0;
assert(checkSudoku(sudoku)==true);
sudoku[0][0] = 8;
assert(checkSudoku(sudoku)==false);
}

л bool checkSudoku (int sudoku[9] [9]) о р о о //check each row for (int i = 0;i<9;i++) { int ung[10] ={0}; for(int j = 0; j<9;j++) { if (sudoku[i][j] = ) { continue; р о л if(ung[sudoku[i][j]] != 0) return false; else ung[sudoku[i][j]]++; о р کا نا نا نا نا نا نا نا نا نا نا نا نا نا نا نا نا نا في ото р // check each column for(int i = 0;i<9;i++) { int ung[10] ={0}; for(int j = 0; j<9;j++) { if(sudoku[j][i] ==0) continue; л о if(ung[sudoku(] [i]] != 0) return false; else ung[sudoku [j][i]]++; р о ذا أما في о во أي أي // check each sub-box أي р أي п int x = 0, y = 0; أي о أي أي р أي while(x9 && y<9) { int ung[10] = {0}; for (int i = x;i<x+3;i++) for(int j = y;j<y+3;j++) { if(sudoku[i][j] ==0) continue; أم potо Activate Windows Go to Settings to activate Windows لم لم

- x D C:\Users\Pankaj\Desktop\ct.cpp - Notepad++ File Edit Search View Encoding Language Settings Tools Macro Run Plugins Window ? OBOBOCCE NOODE php.ini x index.html x index.html x aboutus.html x schedule.html x labpro3-20190601T1104462-001.zip signup.html x signup.php x int ung[10] ={0}; for(int j = 0; j<9; j++) { if(sudoku [j][i] ==O) continue; apply_proxy.sh x look And Say (1).cx i ndex.html x magic.php x Ect.cpp X N N N N N N N if(ung[sudoku(] [i]] != 0) return false; else ung[sudoku[j][i]]++; // check each sub-box mm mm mm mm N O COO in W NOCOO in W int x = 0, y = 0; while(x9 && y<9) { int ung[10] = {0}; for(int i = x;i<x+3;i++) for(int j = y;j<y+3; j++) { if (sudoku[i][j] ==0) continue if(ung[sudoku[i][j]] != 0) return false; else ung[sudoku[i][j]]++; x += 3; if(x == 9 && y<6){ x = 0; y +=3; OLO Join NO LOCO on N return true; N //square boxes checking C++ source file length: 2,183 lines: 80 Ln: 1 Col:1 Sel: 010 Activate Windows Go to Settings to activate Windows Windows (CRLF) UTF-8 INS AJEM E ENG 12:56 AM IN 28/09/2019 Search the web and Windows