Question Name:GRID CHALLENGE

#define _USE_MATH_DEFINES
#define _CRT_SECURE_NO_DEPRECATE

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <climits>
#include <cfloat>
#include <ctime>
#include <cassert>
#include <map>
#include <utility>
#include <set>
#include <iostream>
#include <memory>
#include <string>
#include <vector>
#include <algorithm>
#include <functional>
#include <sstream>
#include <complex>
#include <stack>
#include <queue>
#include <numeric>
#include <list>
#include <iomanip>
#include <fstream>
#include <iterator>
#include <bitset>

using namespace std;

typedef long long ll;
typedef pair<int, int> Pii;
typedef pair<ll, ll> Pll;

#define FOR(i,n) for(int i = 0; i < (n); i++)
#define sz(c) ((int)(c).size())
#define ten(x) ((int)1e##x)
#define tenll(x) ((ll)1e##x)
template<class T> T gcd(T a, T b) { return b ? gcd(b, a % b) : a; }

void solve(){
 int n; cin >> n;
 vector<string> v(n);
 FOR(i, n) cin >> v[i];
 FOR(i, n) sort(v[i].begin(), v[i].end());
 bool b = true;
 FOR(i, n){
  string x;
  FOR(j, n) x.push_back(v[j][i]);
  string y = x;
  sort(y.begin(), y.end());
  if (x != y) {
   b = false;
  }
 }
 puts(b ? "YES" : "NO");
}

int main(){
 int t; cin >> t;
 while (t--) {
  solve();
 }
 return 0;
}

• Problem Description
  Given a squared sized grid G of size N in which each cell has a lowercase letter. Denote the character in the ith row and in the jth column as G[i][j].
  
  You can perform one operation as many times as you like: Swap two column adjacent characters in the same row G[i][j] and G[i][j+1] for all valid i,j.
  
  Is it possible to rearrange the grid such that the following condition is true?
  G[i][1]<=G[i][2]<=…<=G[i][N] for 1<=i<=N and
  
  G[1][j]<=G[2][j]<=…<=G[N][j] for 1<=j<=N
  
  In other words, is it possible to rearrange the grid such that every row and every column is lexicographically sorted?
  
  Note:c1<=c2 , if letter c1 is equal to c2 or is before c2 in the alphabet.
  
  Input Format
  
  The first line begins with T, the number of testcases. In each testcase you will be given N. The following N lines contain N lowercase english alphabet each, describing the grid.
  
  Constraints
  1<=T<=100
  1<=N<=100
  
  Gij will be a lower case letter
  
  Output Format
  
  Print T lines. On the ith line print YES if it is possible to rearrange the grid in the ith testcase or NO otherwise.
• Test Case 1
  Input (stdin)  1
  5
  ebacd
  fghij
  olmkn
  trpqs
  xywuv
  Expected OutputYES
• Test Case 2
  Input (stdin)1
  3
  fghij
  ebacd
  olmkn
  Expected OutputNO