15 Puzzle, Solvable or not??

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#include<bits/stdc++.h> #define MX 1000007 #define ll long long #define ull unsigned long long #define fori(a,n) for(int i=a;i<n;i++) #define forj(a,n) for(int j=0;j<n;j++) using namespace std; int x,n; int inCount(int *a) { int cnt=0; for(int i=0;i<x;i++){ for(int j=i+1;j<x;j++) if(a[i]>a[j] && a[i] && a[j]) cnt++; } return cnt; } int main() { int position; cin>>n; int ara[n][n],trace[n*n]; for(int i=0;i<n;i++){ for(int j=0;j<n;j++){ cin>>ara[i][j]; trace[x++]=ara[i][j]; if(ara[i][j]==0) position=n-i; } } cout<<"Position "<<position<<endl; int cnt=inCount(trace); cout<<"Invertion: "<<cnt<<endl; if(n&1 && cnt%2==0) cout<<"Solveable!"<<endl; else if(n%2==0 && cnt%2==0 && position%2==1) cout<<"Solvable!"<<endl; else if(n%2==0 && cnt%2==1 && position%2==0) cout<<"Solvable!"<<endl; else cout<<"Unsolvable!"<<endl; return 0; }