好的-是的,这是家庭作业,但不是我的。我有一个朋友在参加C ++入门课程,他向我寻求帮助,我帮助他们编写了该程序,但是有一个奇怪的错误我无法弄清。任何有用的建议将不胜感激。谢谢!!
以下是代码。问题在于,在add_loop函数之后,int loop_size将获得一个随机值。在函数内,它具有应该具有的值,但之后它会更改。
#include <iostream>
#include <string>
#include <stdlib.h>
#include <time.h>
using namespace std;
#define STRING_SIZE 50
void get_template (char StemLoop [])
{
char Template [STRING_SIZE];
cout<<"Please enter a template for the stem:";
cin>> Template;
strcpy (StemLoop, Template);
}
void add_loop (char StemLoop[], int loop_size)
{
char random_loop [STRING_SIZE];
int random_array[STRING_SIZE];
for (int i=0; i<loop_size; i++)
{
random_array[i] = rand() % 4;
if (random_array[i]==0)
random_loop[i]='A';
else if (random_array[i]==1)
random_loop [i]='U';
else if (random_array[i]==2)
random_loop [i]='G';
else if (random_array[i]==3)
random_loop [i]='C';
}
strcat (StemLoop, random_loop);
}
void add_complement(char StemLoop[], int loop_size)
{
int x =strlen(StemLoop);
int j=0;
char complement [STRING_SIZE]="";
for (int i=0; i<(x-loop_size); i++)
{
if (StemLoop[i]=='A')
complement[j]='U';
else if (StemLoop[i]=='U')
complement[j]='A';
else if (StemLoop[i]=='G')
complement[j]='C';
else if (StemLoop[i]=='C')
complement[j]='G';
j++;
}
strcat(StemLoop,complement);
}
void main()
{
int loop_size=0;
cout<<"Please enter the size of the loop: ";
cin>>loop_size;
char StemLoop [STRING_SIZE];
//Part1: the template
get_template (StemLoop);
//This is supposed to be the function that adds the loop of random "genes".
//It works, and within it the int loop_size is the correct value...
add_loop (StemLoop, loop_size);
/*...but here it is a random number. It's as if the random value generated
within the function is getting assigned to it. And of course, it's throwing off the
entire program.
*/
//Part#3: the complement
add_complement (StemLoop, loop_size);
cout<<"The complete stem-loop strand is:"<<StemLoop<<endl;
}
最佳答案
在random_loop
中使用strcat
时,您不会将其终止为0,因此strcat
可以在整个堆栈中进行写入。尝试这个:
random_loop[i] = 0;
strcat (StemLoop, random_loop);
一个更严重的问题可能是您没有检查是否有足够的空间容纳
strcat
。