C++ 讀寫txt文件數據
從一個 txt 文件中讀取數據,將其存入 二維數組;
例:
現有 行數為 200, 列數為 100 的 2個 txt 文檔數據,分別為 1.txt,2.txt, 路徑分別為 D://1.txt, D://2.txt;
將其存入 A,B 數組,並分別寫入 D://A.txt,D://B.txt 之中。
代碼:
#include <iostream> #include <fstream> using namespace std; int n = 200, m = 100;// 行為 200 列為100 double a[205][105], b[205][105]; void readfile() { int cnt = 0; FILE *fp1 = fopen("D://1.txt","r"); for(int i = 1; i <= n; i++) { for(int j = 1; j <= m; j++) { fscanf(fp1, "%lf", &a[i][j]); cnt++; } } FILE *fp2 = fopen("D://2.txt","r"); for(int i = 1; i <= n; i++) { for(int j = 1; j <= m; j++) { fscanf(fp2, "%lf", &b[i][j]); } } FILE *fp3 = fopen("D://3.txt","r"); } void creatfileA() { ofstream outfile ("D://A.txt",ios::in|ios::out|ios::binary); for(int i = 1; i <= n; i++) { for(int j = 1; j <= m; j++){ outfile << a[i][j] << " "; } outfile << "\r\n"; } } void creatfileB() { ofstream outfile ("D://B.txt",ios::in|ios::out|ios::binary); for(int i = 1; i <= n; i++) { for(int j = 1; j <= m; j++){ outfile << b[i][j] << " "; } outfile << "\r\n"; } } int main() { readfile(); creatfileA(); creatfileB(); return 0; }