Codeforces Round #411 (Div. 1), problem: (F) Fake bullions Solution In JAVA

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.StringTokenizer;

public class Div1_411F {

int numTV;
int A;
int B;

ArrayList<Integer>[] tAList;

boolean[][] tVAct;
int[] numM;

int cTime = 0;
int[] disc;
int[] low;

ArrayDeque<Integer> stack = new ArrayDeque<Integer>();

ArrayList<ArrayList<Integer>> sCCs = new ArrayList<ArrayList<Integer>>();

int numC;

boolean[][] compAct;

// represents the minimum and the maximum amounts of active members a tournament vertex can have
int[] min;
int[] max;

long MOD = 1_000_000_007L;

int[][] comb;

void dfs(int cV) {
disc[cV] = low[cV] = cTime++;
stack.push(cV);

for (int adj : tAList[cV]) {
if (disc[adj] == -1) {
dfs(adj);
}
if (low[adj] < low[cV]) {
low[cV] = low[adj];
}
}
if (disc[cV] == low[cV]) {
ArrayList<Integer> cSCC = new ArrayList<Integer>();
while (stack.peek() != cV) {
low[stack.peek()] = Integer.MAX_VALUE;
cSCC.add(stack.pop());
}
low[stack.pop()] = Integer.MAX_VALUE;
cSCC.add(cV);
sCCs.add(cSCC);
}
}

void findSCCs() {
disc = new int[numTV];
low = new int[numTV];
Arrays.fill(disc, -1);

for (int i = 0; i < numTV; i++) {
if (disc[i] == -1) {
dfs(i);
}
}

numC = sCCs.size();
}

int fGCD(int a, int b) {
while (b != 0) {
int t = b;
b = a % b;
a = t;
}
return a;
}

void condenseComps() {
compAct = new boolean[numC][];
for (int cComp = 0; cComp < numC; cComp++) {
ArrayList<Integer> cMems = sCCs.get(cComp);
int cGCD = numM[cMems.get(0)];
for (int j : cMems) {
cGCD = fGCD(cGCD, numM[j]);
}
boolean[] cCompSet = compAct[cComp] = new boolean[cGCD];
for (int cM : cMems) {
for (int sM = 0; sM < numM[cM]; sM++) {
if (tVAct[cM][sM]) {
cCompSet[sM % cGCD] = true;
}
}
}
}
}

void pushConnections() {
boolean[] cSet = compAct[numC – 1];

for (int cComp = numC – 2; cComp >= 0; cComp–) {
boolean[] pSet = cSet;
cSet = compAct[cComp];
int gcd = fGCD(pSet.length, cSet.length);

boolean[] resSet = new boolean[gcd];

for (int i = 0; i < pSet.length; i++) {
if (pSet[i]) {
resSet[i % gcd] = true;
}
}

for (int cRes = 0; cRes < gcd; cRes++) {
if(resSet[cRes]){
for (int cNum = cRes; cNum < cSet.length; cNum += gcd) {
cSet[cNum] = true;
}
}
}
}
}

void findMaxs() {
max = new int[numTV];

for (int cComp = 0; cComp < numC; cComp++) {
int aCnt = 0;
for (boolean b : compAct[cComp]) {
if (b) {
aCnt++;
}
}
for (int cM : sCCs.get(cComp)) {
max[cM] = numM[cM] / compAct[cComp].length * aCnt;
}
}
}

// uses Pascal’s identity
void preComb() {
comb = new int[numTV + 1][];
comb[0] = new int[] { 1 };
for (int i = 1; i <= numTV; i++) {
int[] pRow = comb[i – 1];
int[] cRow = comb[i] = new int[i + 1];
cRow[0] = 1;
for (int j = 1; j < i; j++) {
int val = pRow[j] + pRow[j – 1];
cRow[j] = val < 1_000_000_007 ? val : val – 1_000_000_007;
}
cRow[i] = 1;
}
}

long findAns() {
long ans = 0;

for (int sLws = 0; sLws < numTV; sLws++) {
int sGrt = 0;
int pGrt = 0;
for (int oth = 0; oth < numTV; oth++) {
if (oth == sLws) {
continue;
}
if (min[oth] > max[sLws]) {
if (++sGrt >= A) {
continue;
}
}

// secondary condition in case of equality to prevent overcounting
else if (max[oth] > max[sLws] || (max[oth] == max[sLws] && sLws < oth)) {
pGrt++;
}
}

// condition: B – 1 – sGrt <= numT
int s = B – 1 – sGrt;
for (int numT = s > 0 ? s : 0; numT < B && numT <= pGrt && numT + sGrt < A; numT++) {
ans = (ans + ((long) comb[pGrt][numT]) * comb[sGrt][B – 1 – numT]) % MOD;
}
}
return ans;
}

@SuppressWarnings(“unchecked”)
void execute() throws IOException {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));

StringTokenizer inputData = new StringTokenizer(reader.readLine());
numTV = Integer.parseInt(inputData.nextToken());
A = Integer.parseInt(inputData.nextToken());
B = Integer.parseInt(inputData.nextToken());

tAList = new ArrayList[numTV];

for (int i = 0; i < numTV; i++) {
tAList[i] = new ArrayList<Integer>();
String nLine = reader.readLine();
for (int j = 0; j < numTV; j++) {
if (nLine.charAt(j) == ‘1’) {
tAList[i].add(j);
}
}
}

tVAct = new boolean[numTV][];
numM = new int[numTV];
min = new int[numTV];

for (int i = 0; i < numTV; i++) {
inputData = new StringTokenizer(reader.readLine());
int cNumM = numM[i] = Integer.parseInt(inputData.nextToken());
boolean[] cVAct = tVAct[i] = new boolean[cNumM];

String nLine = inputData.nextToken();
for (int j = 0; j < cNumM; j++) {
if (cVAct[j] = nLine.charAt(j) == ‘1’) {
min[i]++;
}
}
}
reader.close();

findSCCs();
condenseComps();
pushConnections();
findMaxs();
preComb();

long ans = findAns();
System.out.println(ans);
}

public static void main(String[] args) throws IOException {
new Div1_411F().execute();
}

}

Betty Gilpin Says She...

Acclaimed actress Betty Gilpin is known for her fearless...

Why Everyone is Obsessed with the Blind Spot Mirrors

Are you tired of dealing with everyday frustrations that slow down your routine? We've all been...

Why Everyone is Obsessed with the Magnetic Spice Rack

Are you tired of dealing with everyday frustrations that slow down your routine? We've all been...

Why Everyone is Obsessed with the Webcam Cover Slide

Are you tired of dealing with everyday frustrations that slow down your routine? We've all been...

Why Everyone is Obsessed with the Magnetic Cabinet Locks

Are you tired of dealing with everyday frustrations that slow down your routine? We've all been...

Betty Gilpin Says She Was ‘Freaked Out’ Over Prosthetic Genitalia for ‘Office Romance’ Birth Scene

Acclaimed actress Betty Gilpin is known for her fearless performances, but a specific prop on the set of her latest film pushed her well...

Why Everyone is Obsessed with the Microfiber Hair Towel

Are you tired of dealing with everyday frustrations that slow down your routine? We've all been...

Why Everyone is Obsessed with the Vegetable Chopper Pro

Are you tired of dealing with everyday frustrations that slow down your routine? We've all been...

How Nature Imagined the Figment of You

How Nature Imagined the Figment of You: Alan Lightman on Existential Probability In an era marked by rapid technological shifts and constant digital noise, a...

Why Everyone is Obsessed with the Packing Cube Set

Are you tired of dealing with everyday frustrations that slow down your routine? We've all been...