这是我第一次使用 stackoverflow，所以我希望我做对了。我在我的一门课上的 1 个程序遇到了一些问题，我已经完成了另外两个。这是问题 3，如果你转到这个 pdf并向下滚动到问题 3，就会有我用来完成这个程序的信息（但我必须说它写得很糟糕。）无论如何，我得到了这些编译时出现非常奇怪的错误，有没有人有任何理由说明我的代码无法编译/无法工作？该程序的重点是读取样本 dna 输入并将其与其他 2 个输入进行比较。我已经按照说明中的说明制作了一个示例文件。感谢您的时间！
我得到了什么错误：
dna.c: In function ‘main’:
dna.c:12: error: expected ‘]’ before ‘;’ token
dna.c:13: error: expected ‘]’ before ‘;’ token
dna.c:14: error: expected ‘]’ before ‘;’ token
dna.c:15: error: expected ‘]’ before ‘;’ token
dna.c:21: error: ‘first’ undeclared (first use in this function)
dna.c:21: error: (Each undeclared identifier is reported only once
dna.c:21: error: for each function it appears in.)
dna.c:22: error: ‘second’ undeclared (first use in this function)
dna.c:23: error: ‘third’ undeclared (first use in this function)
dna.c:25: error: ‘last’ undeclared (first use in this function)
dna.c: In function ‘read_DNA’:
dna.c:43: error: expected ‘)’ before ‘;’ token
dna.c:43: error: too few arguments to function ‘fgets’
dna.c:45: error: expected expression before ‘;’ token
dna.c: In function ‘print_DNA’:
dna.c:76: error: expected ‘)’ before ‘;’ token
这是我的代码
#include <stdio.h>
#define MAX_IN_LENGTH 241;
#define OUT_LENGTH 60;
FILE *input;
FILE *output;
int read_DNA(char sequence[]);
double compare_DNA(char seq1[], char seq2[], char seq3[], int n);
void print_DNA(char seq1[], char seq2[], char seq3[], int n);
int main()
{
char first[MAX_IN_LENGTH];
char second[MAX_IN_LENGTH];
char third[MAX_IN_LENGTH];
int last[MAX_IN_LENGTH];
int i;
int length;
double percent;
input = fopen("dna_input.dat", "r");
output = fopen("dna_output.dat", "w");
length =read_DNA(first);
length =read_DNA(second);
length =read_DNA(third);
fprintf(output,"Comparison between sequence # 1 and sequence #2:\n");
percent=compare_DNA(first, second, last,length);
print_DNA(first, second, last, length);
fprintf(output,"The overlap percentage is %.1f%%\n",percent*100);
fprintf(output,"Comparison between sequence # 1 and sequence #3:\n");
print_DNA(first, third, last,length);
fprintf(output,"The overlap percentage is %.1f%%\n",percent*100);
fprintf(output,"Comparison between sequence # 2 and sequence #3:\n");
percent=compare_DNA(second,third,last,length);
print_DNA(second, third, last, length);
fprintf(output,"The overlap percentage is %.1f%%\n",percent*100);
fclose(input);
fclose(output);
return 0;
}
int read_DNA(char sequence[])
{
fgets(sequence, MAX_IN_LENGTH, input);
int i;
for(i=0; i<MAX_IN_LENGTH; i++)
{
if(sequence[i]=='\0')
return i;
}
return MAX_IN_LENGTH;
}
double compare_DNA(char seq1[], char seq2[], char seq3[], int n)
{
int i,count=0;
for(i=0;i<n-1;i++)
{
if(seq1[i]==seq2[i])
{
seq3[i]=seq1[i];
count++;
}
else
seq3[i]=' ';
}
return (double)count/(n-1);
}
void print_DNA(char seq1[], char seq2[], char seq3[], int n)
{
int i=0;
int lines, j, start, stop;
lines =n/OUT_LENGTH;
if( n%OUT_LENGTH!=0)
lines++;
for(j=0;j<lines;j++)
{
start=j*OUT_LENGTH;
stop=(j+1)*OUT_LENGTH;
if(stop>=n)
stop=n-1;
for(i=start;i<stop;i++)
fprintf(output,"%c",seq1[i]);
fprintf(output,"\n");
for(i=start;i<stop;i++)
{
fprintf(output,"%c",seq3[i]);
if(seq3[i]==' ')
fprintf(output,"");
}
fprintf(output,"\n");
for(i=start;i<stop;i++)
{
fprintf(output,"%c",seq2[i]);}
fprintf(output,"\n");
}
}