PTA 正整数A+B Java
题的目标很简单,就是求两个正整数A和B的和,其中A和B都在区间[1,1000]。稍微有点麻烦的是,输入并不保证是两个正整数。
输入格式:
输入在一行给出A和B,其间以空格分开。问题是A和B不一定是满足要求的正整数,有时候可能是超出范围的数字、负数、带小数点的实数、甚至是一堆乱码。
注意:我们把输入中出现的第1个空格认为是A和B的分隔。题目保证至少存在一个空格,并且B不是一个空字符串。
输出格式:
如果输入的确是两个正整数,则按格式A + B = 和输出。如果某个输入不合要求,则在相应位置输出?,显然此时和也是?。
输入样例1:
123 456
输出样例1:
123 + 456 = 579
输入样例2:
22. 18
输出样例2:
? + 18 = ?
输入样例3:
-100 blabla bla…33
输出样例3:
? + ? = ?
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.util.StringTokenizer;
public class Main {
public static void main(String[] args) throws IOException {
Reader.init(System.in);
Writer.init(System.out);
slove();
Writer.close();
}
// 解答入口
static void slove() throws IOException {
String str = Reader.nextLine();
String[] strs = str.split(" ");
String aS = strs[0];
String bS = strs[1];
Integer a = null, b = null;
try {
a = Integer.parseInt(aS);
if (a < 1 || a > 1000) {
Writer.print("?");
a = null;
} else {
Writer.print(a);
}
} catch (Exception e) {
Writer.print("?");
}
Writer.print(" + ");
try {
b = Integer.valueOf(bS);
// 避免以空格结尾
if (b < 1 || b > 1000 || strs.length > 2) {
Writer.print("?");
b = null;
} else {
Writer.print(b);
}
} catch (Exception e) {
Writer.print("?");
}
Writer.print(" = ");
if (a == null || b == null)
Writer.print("?");
else
Writer.print(a + b);
}
}
// 以下是输入输出模板和思路逻辑无关
class Reader {
static BufferedReader reader;
static StringTokenizer tokenizer;
static void init(InputStream input) {
reader = new BufferedReader(new InputStreamReader(input));
tokenizer = new StringTokenizer("");
}
static String next() throws IOException {
while (!tokenizer.hasMoreTokens()) {
tokenizer = new StringTokenizer(reader.readLine());
}
return tokenizer.nextToken();
}
static String nextLine() throws IOException {
return reader.readLine();
}
static int nextInt() throws IOException {
return Integer.parseInt(next());
}
static long nextLong() throws IOException {
return Long.parseLong(next());
}
static char nextChar() throws IOException {
return next().toCharArray()[0];
}
static float nextFloat() throws IOException {
return Float.parseFloat(next());
}
static Double nextDouble() throws IOException {
return Double.parseDouble(next());
}
}
class Writer {
static BufferedWriter writer;
static void init(OutputStream outputStream) {
writer = new BufferedWriter(new OutputStreamWriter(outputStream));
}
static void print(Object object) throws IOException {
writer.write(object.toString());
}
static void println(Object object) throws IOException {
writer.write(object.toString());
writer.write("\n");
}
static void close() throws IOException {
writer.close();
}
}