//import java.lang.*;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.PrintStream;
//import java.io.File;
import java.io.PrintWriter;
import java.util.ArrayList;
public class Overflow {
public static void main(String[] args)throws FileNotFoundException {
PrintStream ps=new PrintStream(new FileOutputStream("output.txt"));
System.setOut(ps);
System.out.println("Java");
factByte();
factShort();
factInt();
factLong();
factFloat();
factDouble();
writeCsv();
}
static ArrayList<String> type = new ArrayList<>();
static ArrayList<Integer> nn = new ArrayList<>();
// byte类型
static void factByte(){
int n = 1, max;
byte ans = 1; // n！
while (true) {
byte fact = 1;
for (int i = n; i > 1; i--) {
fact *= i;
}
if (Byte.MAX_VALUE / ans < n) {
max = n - 1;
break;
}
ans = fact;
//System.out.println(n+"!="+fact);
++n;
}
System.out.println("byte\t"+max+"!="+ans);
type.add("byte");
nn.add(max);
}
// short类型
static void factShort(){
int n = 1, max;
short ans = 1; // n！
while (true) {
short fact = 1;
for (int i = n; i > 1; i--) {
fact *= i;
}
if (Short.MAX_VALUE / ans < n) {
max = n - 1;
break;
}
ans = fact;
//System.out.println(n+"!="+fact);
++n;
}
System.out.println("short\t"+max+"!="+ans);
type.add("short");
nn.add(max);
}
// int类型
static void factInt(){
int n = 1, max;
int ans = 1; // n！
while (true) {
int fact = 1;
for (int i = n; i > 1; i--) {
fact *= i;
}
if (Integer.MAX_VALUE / ans < n) {
max = n - 1;
break;
}
ans = fact;
//System.out.println(n+"!="+fact);
++n;
}
System.out.println("int\t"+max+"!="+ans);
type.add("int");
nn.add(max);
}
// long类型
static void factLong(){
int n = 1, max;
long ans = 1; // n！
while (true) {
long fact = 1;
for (int i = n; i > 1; i--) {
fact *= i;
}
if (Long.MAX_VALUE / ans < n) {
max = n - 1;
break;
}
ans = fact;
//System.out.println(n+"!="+fact);
++n;
}
System.out.println("long\t"+max+"!="+ans);
type.add("long");
nn.add(max);
}
// float类型
static void factFloat(){
int n = 1, max;
float ans = 1; // n！
while (true) {
float fact = 1;
for (int i = n; i > 1; i--) {
fact *= i;
}
if (Float.MAX_VALUE / ans < n) {
max = n - 1;
break;
}
ans = fact;
//System.out.println(n+"!="+fact);
++n;
}
System.out.println("float\t"+max+"!="+ans);
type.add("float");
nn.add(max);
}
// double类型
static void factDouble(){
int n = 1, max;
double ans = 1; // n！
while (true) {
double fact = 1;
for (int i = n; i > 1; i--) {
fact *= i;
}
if (Double.MAX_VALUE / ans < n) {
max = n - 1;
break;
}
ans = fact;
//System.out.println(n+"!="+fact);
++n;
}
System.out.println("double\t"+max+"!="+ans);
type.add("double");
nn.add(max);
}
static void writeCsv()throws FileNotFoundException{
PrintWriter pw = new PrintWriter("table.csv");
StringBuilder sb = new StringBuilder();
int count = type.size();
sb.append("type");
sb.append(',');
sb.append("max n\n");
for(int i = 0; i < count; i++){
sb.append(type.get(i));
sb.append(',');
sb.append(nn.get(i));
sb.append('\n');
}
pw.write(sb.toString());
pw.close();
}
}
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