数据分别读取fscanf

我正在尝试从文件中读取数字。 该文件具有以下格式：

2 4 5 7 3 2 4 7 

我尝试使用fscanf来收集到换行符的所有数字并将数字存储在数组中，并将数字存储在第二行。 但直接从第二行继续不再启动并将其存储在另一个数组中。 是否可以使用fscanf执行此操作？

 int main(void) { FILE* fp; int *vec = malloc(sizeof(int)*6); int *vec_2 = malloc(sizeof(int)*6); int row, i; fp = fopen("vector.txt","r"); for(i = 0; i < row; i++) //I don't know how to read until newline fscanf(fp, "%d", &vec[k]); //here store the first row in the array for(i = 0; i < row; i++) fscanf(fp, "%d", &vec_2[i]); //start reading here from the second row free(vec); free(vec_2); return 0; } 

Answer 1

 int main(void){ FILE* fp; int cols = 6; int *vec_1 = malloc(sizeof(int)*cols); int *vec_2 = malloc(sizeof(int)*cols); int i, i1, i2; char ch; fp = fopen("vector.txt","r"); for(i1 = 0; i1 < cols; ){ fscanf(fp, "%d%c", &vec_1[i1++], &ch);//Format is limited. "num[ \t\n]" if(ch == '\n') break; } i2 = 0; while(1==fscanf(fp, "%d", &vec_2[i2])){ if(++i2 == cols) break; } fclose(fp); printf("first : "); for(i=0; i 

Answer 2

任何时候数据都存储fgets() ，最好考虑fgets() 。

该解决方案适应N行和用户可选择的列宽

 #define MAX_INT_WIDTH (sizeof (int) * CHAR_BIT/3 + 3) int **Read_Lines_Of_Numbers(FILE* inf, size_t Expected_Row_Width) { int **Row = NULL; size_t RowCount = 0; size_t RowSize = 0; char buf[Expected_Row_Width * (MAX_INT_WIDTH + 1) + 2]; while (fgets(buf, sizeof buf, inf) != NULL) { if (RowCount >= RowSize) { RowSize = (RowSize + 1) * 2; // Double size Row = realloc(Row, RowSize * sizeof *Row); // OOM checking omitted } Row[RowCount] = calloc(Expected_Row_Width, sizeof *Row[RowCount]); // OOM checking omitted size_t i; char *p = buf; for (i = 0; i < Expected_Row_Width; i++) { int n; if (sscanf(p, "%d %n", &Row[RowCount][i], &n) != 1) break; p += n; } if (*p || i != Expected_Row_Width) { // Bad data on line free(Row); return NULL; } RowCount++; } Row = realloc(Row, (RowCount + 1) * sizeof *Row); // OOM checking omitted Row[RowCount] = NULL; return Row; } int main(void) { FILE *inf = fopen("c:/tmp/vector.txt", "r"); size_t Width = 4; int **Data = Read_Lines_Of_Numbers(inf, Width); fclose(inf); if (Data) { size_t i; for (i = 0; Data[i]; i++) { size_t j; for (j = 0; j < Width; j++) { printf(" %d", Data[i][j]); } fputc('\n', stdout); } free(Data); } return 0; } 

Answer 3

行必须初始化为6并且可能也是col，您可以使用以下二维数组。

 int main() { FILE* fp; int **vec; int row = 6, col = 6, i, j; vec = malloc(sizeof(int *)*row); // allocates space for each row for (i = 0; i < row; i++) { vec[i] = malloc(sizeof(int)*col); // now allocate space for each cell within a row } fp = fopen("vector.txt","r"); for(i = 0; i < row; i++) { for (j=0; j < col; j++) { fscanf(fp, "%d", &vec[i][j]); // read ith row, jth col } } vec = malloc(sizeof(int *)*row); for (i = 0; i < row; i++) { free(vec[i]); } free(vec); return 0; }