hw

#include <sys/wait.h>
#include <iostream>
#include <unistd.h>
#include <stdio.h>
#include <cstdlib>
#include <string.h>

using namespace std;

char** getlastline(int& l){
    char** ans=NULL;
    char c;
    l=0;
    while(true){
        cin>>c;
        while (c==' ') cin>>c;
        if ((c=='\n') || (c==-1))
            break;
        char* word;
        int wlength=0;
        while ((c!=' ') && (c!='\n') && (c!=-1)){
            if (wlength==0)
                word=(char *)malloc(sizeof(char));
            else
                word=(char *)realloc(word, (wlength+1)*sizeof(char));
            word[wlength++]=c;
            cin>>c;
        }
        if (wlength!=0){
            if (l==0)
                ans=(char**)malloc(sizeof(char*));
            else
                ans=(char**)realloc(ans, (l+1)*sizeof(char));
            ans[l++]=(char*)malloc((wlength+1)*sizeof(char));
            strcpy(ans[l-1], word);
        }
        cout<<word<<endl;
        free(word);
    }
    if (l!=0){
        ans=(char**)realloc(ans, (l+1)*sizeof(char));
        ans[l++]=(char*)malloc(sizeof(char));
        ans[l-1]=NULL;
    }
    return ans;
}

int main(){
    int n;
    while (true){
        int l=0;
        char** s=getlastline(l);
        if (l==0)
            return 1;
        n=fork();
        int status;
        if (n==0){
            if (execvp(s[0], s) == -1){
                perror("exec ");
                return 1;
            }
        }
        else
            wait(&status);
        if (!WIFEXITED(status) || WEXITSTATUS(status)){
            cout<<"It all went wrong!";
            return 1;
        }
        for (int i=0; i<l; i++)
            free(s[i]);
        free(s);
    }
    return 0;
}