C语言怎样利用数组处理数据？

Posted 2023-03-09

如上图所示，读取一个txt文件，如何得到下图内容（如果每行前两列相同，比较第三列，大者输出，如果不同，逐行输出）？

参考技术A #include
#include

long ToLong(char *s)
long i = 0,num = 0;
while(s[i])
if(s[i] >= 'a' && s[i] <= 'f')
num = 16 * num + s[i] - 'a' + 10;
else if(s[i] >= 'A' && s[i] <= 'F')
num = 16 * num + s[i] - 'A' + 10;
else if(s[i] >= '0' && s[i] <= '9')
num = 16 * num + s[i] - '0';
++i;

return num;


int main()
char s[81];
enum MAXLEN = 500;
long num[MAXLEN],i,cnt = 0,n = 0;
FILE *infp = fopen("source.txt","rt");
FILE *outfp = fopen("result.txt","wt");
if(infp == NULL || outfp == NULL)
printf("打开文件失败!\n");
return 1;

while(!feof(infp))
fgets(s,81,infp);
num[n++] = ToLong(s);

fclose(infp);
for(i = 0; i < n; ++i)
if(cnt && cnt % 20 == 0)
fprintf(outfp,"\n");
printf("\n");

fprintf(outfp,"%ld ",num[i]);
printf("%ld ",num[i]);

fclose(outfp);
return 0;
追问

输出结果不对啊？