学步园

#include <cstdlib><br /> #include <iostream><br /> #include <assert.h><br /> using namespace std;<br /> class mystack<br /> {<br /> public:<br /> mystack(int _n)<br /> {<br /> n = _n;<br /> arr = new int[_n];<br /> memset(arr, 0, n);<br /> size1 = -1;<br /> size2 = _n;<br /> }<br /> void push1(int element)<br /> {<br /> if(size2 - size1 > 1)<br /> {<br /> size1++;<br /> arr[size1] = element;<br /> }<br /> }<br /> void pop1()<br /> {<br /> if(size1 >= 0)<br /> {<br /> arr[size1] = 0;<br /> size1--;<br /> }<br /> }<br /> int top1()<br /> {<br /> assert(size1 >= 0);<br /> return arr[size1];<br /> }<br /> bool empty1()<br /> {<br /> return !(size1 >= 0);<br /> }<br /> /*第二个栈*/<br /> void push2(int element)<br /> {<br /> if(size2 - size1 > 1)<br /> {<br /> size2--;<br /> arr[size2] = element;<br /> }<br /> }<br /> void pop2()<br /> {<br /> if(size2 <= n-1)<br /> {<br /> arr[size2] = 0;<br /> size2++;<br /> }<br /> }<br /> int top2()<br /> {<br /> assert(size2 <= n-1);<br /> return (arr[size2]);<br /> }<br /> bool empty2()<br /> {<br /> return !(size2 < n);<br /> }<br /> ~mystack()<br /> {<br /> delete []arr;<br /> }<br /> private:<br /> int *arr;<br /> int size1;<br /> int size2;<br /> int n;<br /> };<br /> int main(int argc, char *argv[])<br /> {<br /> mystack my(20);<br /> for(int i=0; i<6; i++)<br /> {<br /> my.push1(i);<br /> my.push2(20 - i);<br /> }<br /> while (!my.empty1())<br /> {<br /> cout<<my.top1()<<" ";<br /> my.pop1();<br /> }<br /> cout<<endl;<br /> while (!my.empty2())<br /> {<br /> cout<<my.top2()<<" ";<br /> my.pop2();<br /> }<br /> cout<<endl;<br /> system("PAUSE");<br /> return EXIT_SUCCESS;<br /> }<br />