将二维数组传递给函数

Question

我正在尝试使用 c

#include <stdio.h>
int getWordAmount(FILE *file);
void getWords(char names[][]);

int main() {
    FILE *file = fopen("files/country.txt", "a+");
    if(file != NULL) printf("File is opened\n");
    else printf("Error occured in opening file\n");
    int n = getWordAmount(file);
    char names[n][20];
    getWords(names);

    for(int i = 0; i < n; i++) {
        for(int j = 0; names[i][j] != '[=10=]'; j++) {
            printf("%c", names[i][j]);
        }
    }
    return 0;
}

int getWordAmount(FILE *file) {
    char c;
    int charAmount = 0;
    while ((c = getc(file)) != EOF) {
        if((c == ' ')||(c == '\n')) charAmount++;
    }
    return charAmount;
}

void getWords(char names[][]) {
    int i = 0, j = 0, k = 0;
    char temp[20];
    while ((c = getc(file)) != EOF) {
        temp[i++] = c;
        if((c == ' ')||(c == '\n')) {
            i = 0;
            while((temp[i] != ' ')||temp[i] != '\n') {
                names[j][k++] = temp[i++];
            }
            j++;
            i = 0;
        }
    }
}

我收到如下所示的错误

E:\Programming\C Files\files.c:3:20: error: array type has incomplete element type 'char[]' 3 | void getWords(char names[][]); | ^~~ E:\Programming\C Files\files.c:3:20: note: declaration of 'names' as multidimensional array must have bounds for all dimensions except the first E:\Programming\C Files\files.c: In function 'main': E:\Programming\C Files\files.c:11:12: error: type of formal parameter 1 is incomplete 11 | getWords(names); | ^ E:\Programming\C Files\files.c: At top level: E:\Programming\C Files\files.c:30:20: error: array type has incomplete element type 'char[]' 30 | void getWords(char names[][]){ | ^ E:\Programming\C Files\files.c:30:20: note: declaration of 'names' as multidimensional array must have bounds for all dimensions except the first E:\Programming\C Files\files.c: In function 'getWords': E:\Programming\C Files\files.c:33:11: error: 'c' undeclared (first use in this function) 33 | while ((c = getc(file)) != EOF){ | ^ E:\Programming\C Files\files.c:33:11: note: each undeclared identifier is reported only once for each function it appears in E:\Programming\C Files\files.c:33:20: error: 'file' undeclared (first use in this function); did you mean 'fileno'? 33 | while ((c = getc(file)) != EOF){ | ^~ | fileno

这是我的country.txt

Bangladesh India China Nepal Bhutan
Pakistan Indonesia America Miyanmar
USA North-Korea South-korea Brazil
Argentina
Indonesia Japan Singapur Africa Rassia

Answer 1

正如您所看到的错误，多维数组的声明必须对除第一个维度之外的所有维度都有边界。所以你可以这样做（你的问题的方法之一和最简单的方法）：

// in your case the 20 is second dimension
void getWords(char names[][20]) {
    int i = 0, j = 0, k = 0;
    char temp[20];
    while ((c = getc(file)) != EOF) {
        temp[i++] = c;
        if((c == ' ')||(c == '\n')) {
            i = 0;
            while((temp[i] != ' ')||temp[i] != '\n') {
                names[j][k++] = temp[i++];
            }
            j++;
            i = 0;
        }
    }
}

将二维数组传递给函数

Passing 2 dimensional array to function

arrays

c

function

pointers

2d