题解 | #句子逆序#

#include <stdio.h>
#include <stdlib.h>
struct Sentense
{
    char **words;
    char * str;
    unsigned short length;
    int top;
    int strCount;
};
int main() {
    struct Sentense sentense;
    sentense.top=-1;
    sentense.strCount=0;
    sentense.length=100;
    sentense.words=(char **)malloc(sentense.length*sizeof(char *));
    sentense.str = (char*)malloc(1000*sizeof(char));

    
    while(1)
    {
        char c=getchar();
        static unsigned short wordCount=0;        
        if(c!=' '&&c!='\n')
        {
            wordCount++;
            sentense.str[sentense.strCount++]=c;
        }
        else
        {
            wordCount++;
            sentense.str[sentense.strCount++]='\0';
            //如果堆栈不够大，拓展堆栈
            if(sentense.top>=sentense.length-1){
                sentense.length+=100;
                sentense.words = (char **)realloc(sentense.words, sentense.length*sizeof(char *));
            }
            sentense.words[++sentense.top]=sentense.str+sentense.strCount-wordCount;
            wordCount = 0;
            if(c=='\n')
                break;
        } 
    }
    while(sentense.top>=0)
    {
        printf("%s ",sentense.words[sentense.top--]);
    }
    return 0;
}