[問題] fstream eof 的問題 [已解決]

看板C_and_CPP (C/C++)作者Au2 (兩金)時間15年前 (2010/10/19 09:43)推噓1(1推 0噓 13→)

留言14則, 3人參與討論串1/1

看似簡單的邏輯, 試了很多種方法還是沒有解決, 煩請前輩們指點迷津 m(_._)m 需求 : 讀入一個 .txt 檔案如下前面是學號, 後面是成績計算出每個學生個人成績以及各科平均 1001 3.0 2.7 2.0 2.8 1002 3.7 3.5 4.0 4.0 1003 0.0 1.0 2.2 1.0 1004 4.0 3.0 3.5 3.5 問題 : 用 while 設定在 EOF 的時候跳出, 可是程式會把最後一筆資料再讀一次請問要怎麼加上條件能避免這樣的情形呢 ? 輸出檔案 : 1001 2.625 1002 3.800 1003 1.050 1004 3.500 1004 3.500 <- 會把最後一筆資料再讀一次 Average 1 = 2.940 Average 2 = 2.640 Average 3 = 3.040 Average 4 = 2.960 請按任意鍵繼續 . . . 程式碼 : #include <iostream> #include <fstream> #include <iomanip> #define INPUT_FILE_LOCATION "e:\\InTest.txt" #define OUTPUT_FILE_LOCATION "e:\\OUT.txt" #define ERROR_MSG "Error" using namespace std; int main(){ int studentID; int count=0; double personalAve; double g1, g2, g3, g4; double ave1=0, ave2=0, ave3=0, ave4=0; double sum1=0, sum2=0, sum3=0, sum4=0; fstream inFile(INPUT_FILE_LOCATION); ofstream outFile(OUTPUT_FILE_LOCATION); if(!inFile || !outFile) cout << ERROR_MSG << endl; else{ while (!inFile.eof()){ outFile << fixed << setprecision(3); inFile >> studentID >> g1 >> g2 >> g3 >> g4; personalAve = (g1 + g2 + g3 + g4)/4; outFile << studentID << "\t" << personalAve << endl; count++; sum1 = sum1 + g1; sum2 = sum2 + g2; sum3 = sum3 + g3; sum4 = sum4 + g4; ave1 = sum1 / count; ave2 = sum2 / count; ave3 = sum3 / count; ave4 = sum4 / count; } outFile << "\nAverage 1 = " << ave1 << endl; outFile << "Average 2 = " << ave2 << endl; outFile << "Average 3 = " << ave3 << endl; outFile << "Average 4 = " << ave4 << endl; outFile << "\n\n" ; } inFile.close(); system("PAUSE"); return 0; } -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 24.218.207.96