迭代连接两个字符串 - C

Question

我想迭代一个字符串(由用户输入)，返回输入的字符串，并在每个字符后添加空格。 IE。 “你好”-->“你好”。

我的 C 代码:

#include <stdio.h>
#include <string.h>

int main()
{
    char str[] = "";
    printf("Enter a string: ");
    scanf("%s", &str);

    int i = 0;
    char newstr[150] = "";

    for (i = 0; i < strlen(str); i++)
    {
        strcat(newstr, str[i]);
        strcat(newstr, " ");
    }

    printf("Expanded String: ");
    printf("%s", newstr);

    return 0;
}

我的错误如下:

warning: passing argument 2 of ‘strcat’ makes pointer from integer without a cast [enabled by default] ----- > strcat(newstr, str[i]);

note: expected ‘const char *’ but argument is of type ‘char’ ----- > char *_EXFUN(strcat,(char *__restrict, const char *__restrict));

我习惯了可以连接字符串索引的 python 语法，这是我的 C 代码出错的地方吗？

Answer 1

for (i = 0; i < strlen(str); i++)
{
    newstr[2*i]=str[i];
    newstr[2*i+1]=' ';
}
// newstr[2 * strlen(str)] = '\0';
// thanks for the hint - I omit that because
// the whole buffer had been cleared during initialization