C/C++ 格式化读取和读取一行

文件内容

2
3 2
1 4 1 1 0 11
4 1 1 1 8 11
2 5 0 0 0 11
4 1 0 0 0 11
5 5
2 4 1 0 1 13
4 4 0 1 12 13
1 4 1 1 0 13
3 5 1 1 7 13

一、格式读取

1. C语言

FILE * f_in = fopen("1.txt", "r");
    int k;
    int m, n;
    int dp[];
    fscanf(f_in, "%d", &k);
    while (k--) {
        fscanf(f_in, "%d %d", &m, &n);
        for (int i = ; i < ; ++i) {
            fscanf(f_in, "%d %d %d %d %d %d", &dp[], &dp[], &dp[], &dp[], &dp[], &dp[]);
        }
    }

2. C++  >>输入运算符遇到空白字符就停止输入，但把空白字符留在缓冲区

ifstream f_in("1.txt");
    int k;
    int m, n;
    int dp[];
    f_in >> k;
    while (k--) {
        f_in >> m >> n;
        for (int i = ; i < ; ++i) {
            f_in >> dp[] >> dp[] >> dp[] >> dp[] >> dp[] >> dp[];
            cout << dp[] << "," << dp[] << "," << dp[] << "," << dp[] << "," << dp[] << "," << dp[] << endl;
        }
    }

二、读取一行

C++

getline一直读到换行符，从输入缓存读取换行符并把换行符丢弃

    ifstream f_in("1.txt");

    string str;

    while (getline(f_in, str)){
            cout << str << endl;

    }    

C语言 fgets读取并丢掉换行符

FILE* f_in = fopen("1.txt", "r");

    char str[];

    while (fgets(str, , f_in)){
        cout << str;
    }