括弧匹配（棧實現）

 

#include <cstdio>#include <iostream>using namespace std;#define MAXSIZE 20typedef struct {char *base;char *top;int stacksize;}SqStack;void InitStack(SqStack &S){S.base = (char *)malloc( MAXSIZE * sizeof(char) );if(S.base == NULL)exit(-2);S.top = S.base;S.stacksize = MAXSIZE;}void GetTop(SqStack S, char &e){if(S.top == S.base)return;e = *(S.top - 1);}void Push(SqStack &S, char e)//不考慮棧滿{*S.top++ = e;}void Pop(SqStack &S, char &e){if(S.top == S.base)return;S.top--;e = *S.top;}bool Match(char c, SqStack &my_stack, bool &tag){char e;Pop(my_stack, e);if ( c != e ) {tag = false;free(my_stack.base);return false;//match fail}return true;//match success}void Correct(char *expr, bool &tag){tag = true;SqStack my_stack;InitStack (my_stack);for( int i = 0; expr[i] != '\0'; i++ ) {char c = expr[i];switch(c) {case '{' : case '[' : case '(' :Push (my_stack, c); break;case '}' : if( Match('{', my_stack, tag) == false )//match failreturn;break;case ']' : if( Match('[', my_stack, tag) == false )//match failreturn;break;case ')' : if( Match('(', my_stack, tag) == false )//match failreturn;break;default :break;//其它字元}}if(my_stack.top != my_stack.base)// e.g.: "[r"tag = false;free(my_stack.base);}int main(void){//freopen("cin.txt", "r", stdin);char my_expr[MAXSIZE];while(cin >> my_expr) {bool tag = true;Correct( my_expr, tag);tag ? printf("匹配成功\n") : printf("匹配失敗\n");}return 0;}

 

 

（另見 http://blog.csdn.net/justme0/article/details/7424798）