36 lines
683 B
C
36 lines
683 B
C
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#include <stdio.h>
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#include <stdlib.h>
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// 实现读取 filepath 文件的前 top_n 行数据
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void *read_top_line(const char *filepath, int top_n)
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{
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FILE *f = fopen(filepath, "r");
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if (NULL == f)
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{
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perror("fopen");
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return NULL;
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}
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char(*lines)[100] = calloc(top_n, 100);
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for (int i = 0; i < top_n; i++)
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{
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char *flag = fgets(lines[i], 100, f);
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if (flag == NULL)
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break;
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}
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fclose(f);
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return lines;
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}
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int main()
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{
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int n = 5;
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char(*p)[100] = read_top_line("d10.txt", n);
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for (int i = 0; i < n; i++)
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{
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printf("第 %d 行: %s", i + 1, *(p + i));
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}
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free(p);
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return 0;
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}
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