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| #include <bits/stdc++.h>
using namespace std;
typedef pair<long long, long long> pll;
typedef long long ll;
#define S second
#define F first
#define mp make_pair
pll operator-(const pll &a, const pll &b) {
ll g = b.S/__gcd(abs(a.S), b.S)*a.S;
ll x = a.F*g/a.S-b.F*g/b.S, y = g;
g = __gcd(abs(x), y);
return mp(x/g, y/g);
}
pll operator*(const pll &a, const pll &b) {
ll x = a.F*b.F;
ll y = a.S*b.S;
if(y < 0) y*=-1, x*=-1;
ll g = __gcd(abs(x), y);
return mp(x/g, y/g);
}
ostream &operator<<(ostream &out, const pll &a) {
if(a.S == 1)
out << a.F;
else
out << a.F << '/' << a.S;
return out;
}
pll operator/(const pll &a, const pll &b) {
ll x = a.F*b.S;
ll y = a.S*b.F;
if(y < 0) y*=-1, x*=-1;
ll g = __gcd(abs(x), y);
return mp(x/g, y/g);
}
signed main() {
ios::sync_with_stdio(0); cin.tie(0);
int n;
cin >> n;
vector<vector<pll>> arr(n, vector<pll>(n+1));
for(int i = 0; i < n; i++)
for(int j = 0, a; j < n+1; j++)
cin >> a, arr[i][j]=mp(a, 1);
for(int i = 0; i < n; i++) {
bool can = 0;
for(int j = i; j < n; j++) {
if(arr[j][i].F != 0) {
if(i!=j)
swap(arr[i], arr[j]);
can = 1;
break;
}
}
if(!can) {
continue;
}
for(int j = 0; j < n; j++) {
if(i == j)
continue;
auto x = arr[j][i]/arr[i][i];
for(int k = 0; k < n+1; k++)
arr[j][k] = (arr[j][k]-(arr[i][k]*x));
}
}
for(int i = 0; i < n; i++) {
bool can = 0;
for(int j = 0; j < n; j++)
can|=arr[i][j].F;
if(!can) {
if(arr[i][n].F)
return cout << '0', 0;
else
return cout << 'N', 0;
}
}
for(int i = 0; i < n; i++) {
if(!arr[i][i].F)
return cout << 'N', 0;
}
cout << "1\n";
for(int i = 0; i < n; i++) {
cout << 'x' << i+1 << " = " << arr[i][n]/arr[i][i] << '\n';
}
return 0;
}
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