Implement a Simple Shell Command Parser

Code

#include <stdio.h>
#include <ctype.h>

void parse_shell_input(char *str) {
    int i,j;
    for(i=0;str[i]!=0;i++){
        if(str[i]==' '){
            if(str[i+1]==' '){
                for(j=i+1;str[j]!=0;j++){
                    str[j]=str[j+1];
                }
                i--;
            }
            else{
                str[i]='\n';
            }
        }
    }
    printf("%s",str);
}

int main() {
    char line[101];
    fgets(line, sizeof(line), stdin);

    parse_shell_input(line);
    return 0;
}

Solving Approach