C++_USACO_从文件读出两数，相加输出到另一个文件

#include<iostream>
#include<fstream>
#include<string>
using namespace std;
int main(){
ofstream ofs("text.out");
ifstream ifs("text.in");
int a,b;
ifs>>a>>b;
ofs<<a+b<<endl;
return 0;
}

上面是C++。文件格式可以是.txt，也可以使用任意的后缀，采用.in后缀生成IN文件，采用.out后缀生成OUT文件。可以用记事本、Notepad++等打开

下面是C。

/*
ID: your_id_here
LANG: C
TASK: test
*/
#include <stdio.h>
main () {
    FILE *fin  = fopen ("test.in", "r");
    FILE *fout = fopen ("test.out", "w");
    int a, b;
    fscanf (fin, "%d %d", &a, &b);    /* the two input integers */
    fprintf (fout, "%d\n", a+b);
    exit (0);
}

下面是JAVA。

/*
ID: your_id_here
LANG: JAVA
TASK: test
*/
import java.io.*;
import java.util.*;

class test {
  public static void main (String [] args) throws IOException {
    // Use BufferedReader rather than RandomAccessFile; it's much faster
    BufferedReader f = new BufferedReader(new FileReader("test.in"));
                                                  // input file name goes above
    PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("test.out")));
    // Use StringTokenizer vs. readLine/split -- lots faster
    StringTokenizer st = new StringTokenizer(f.readLine());
                          // Get line, break into tokens
    int i1 = Integer.parseInt(st.nextToken());    // first integer
    int i2 = Integer.parseInt(st.nextToken());    // second integer
    out.println(i1+i2);                           // output result
    out.close();                                  // close the output file
    System.exit(0);                               // don't omit this!
  }
}