fix errors in matrix_exponentiation

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Krishna Vedala 2020-06-24 18:27:01 -04:00
parent 46854f516e
commit a190674131
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@ -36,21 +36,18 @@ using std::vector;
#define endl std::endl
/*! shorthand definition for `int64_t` */
#define pb push_back
#define pb push_back
#define MOD 1000000007
/** returns absolute value */
inline ll ab(ll x) { return x > 0LL ? x : -x; }
/** global variable k
/** global variable mat_size
* @todo @stepfencurryxiao add documetnation
*/
ll k;
ll mat_size;
/** global vector variables
/** global vector variables used in the ::ans function.
* @todo @stepfencurryxiao add documetnation
*/
vector<ll> a, b, c;
vector<ll> fib_b, fib_c;
/** To multiply 2 matrices
* \param [in] A matrix 1 of size (m\f$\times\f$n)
@ -59,10 +56,10 @@ vector<ll> a, b, c;
*/
vector<vector<ll>> multiply(const vector<vector<ll>> &A,
const vector<vector<ll>> &B) {
vector<vector<ll>> C(k + 1, vector<ll>(k + 1));
for (ll i = 1; i <= k; i++) {
for (ll j = 1; j <= k; j++) {
for (ll z = 1; z <= k; z++) {
vector<vector<ll>> C(mat_size + 1, vector<ll>(mat_size + 1));
for (ll i = 1; i <= mat_size; i++) {
for (ll j = 1; j <= mat_size; j++) {
for (ll z = 1; z <= mat_size; z++) {
C[i][j] = (C[i][j] + (A[i][z] * B[z][j]) % MOD) % MOD;
}
}
@ -94,24 +91,24 @@ vector<vector<ll>> power(const vector<vector<ll>> &A, ll p) {
ll ans(ll n) {
if (n == 0)
return 0;
if (n <= k)
return b[n - 1];
if (n <= mat_size)
return fib_b[n - 1];
// F1
vector<ll> F1(k + 1);
for (ll i = 1; i <= k; i++) F1[i] = b[i - 1];
vector<ll> F1(mat_size + 1);
for (ll i = 1; i <= mat_size; i++) F1[i] = fib_b[i - 1];
// Transpose matrix
vector<vector<ll>> T(k + 1, vector<ll>(k + 1));
for (ll i = 1; i <= k; i++) {
for (ll j = 1; j <= k; j++) {
if (i < k) {
vector<vector<ll>> T(mat_size + 1, vector<ll>(mat_size + 1));
for (ll i = 1; i <= mat_size; i++) {
for (ll j = 1; j <= mat_size; j++) {
if (i < mat_size) {
if (j == i + 1)
T[i][j] = 1;
else
T[i][j] = 0;
continue;
}
T[i][j] = c[k - j];
T[i][j] = fib_c[mat_size - j];
}
}
// T^n-1
@ -119,7 +116,7 @@ ll ans(ll n) {
// T*F1
ll res = 0;
for (ll i = 1; i <= k; i++) {
for (ll i = 1; i <= mat_size; i++) {
res = (res + (T[1][i] * F1[i]) % MOD) % MOD;
}
return res;
@ -133,19 +130,19 @@ int main() {
cin >> t;
ll i, j, x;
while (t--) {
cin >> k;
for (i = 0; i < k; i++) {
cin >> mat_size;
for (i = 0; i < mat_size; i++) {
cin >> x;
b.pb(x);
fib_b.pb(x);
}
for (i = 0; i < k; i++) {
for (i = 0; i < mat_size; i++) {
cin >> x;
c.pb(x);
fib_c.pb(x);
}
cin >> x;
cout << ans(x) << endl;
b.clear();
c.clear();
fib_b.clear();
fib_c.clear();
}
return 0;
}