void Graph<Tv, Te>::pfs(int s, PU prioUpdater){ //assert: 0 <= s < n
reset(); int v = s; //初始化
do{ //逐一检查所有顶点
if( UNDISCOVERED == status(v)) //一旦遇到尚未发现的节点
PFS(v, prioUpdater); //即从该节点出发启动一次PFS
}while(s != ( v = (++v % n))); //按序号检查,故不漏不重
}
int main(int argv,char *argc[]){
if(argv<2){
PFS("the parameter error");
exit(-1);
}
//读取文件
FILE * fp = fopen(argc[1],"r");
if(fp==NULL){
PFS("open the file error");
exit(-2);
}
int cur_pointer=0; //临时字符的位置游标
int ch=0; //当前读取的字符
char temp[100]; //临时字符存放
int status=0; //状态分四种 0为空白 1为字符 2为数字 3为其他字符
int status__=0; //当status为3时 还细分多字符操作符和单字符操作符
void *elements[1000]; //存放各元素的主字符串指针数组(token值)
int i=0; //主字符串指针数组和syn值数组的当前索引(两数组同步)
int syn[1000]; //syn值数组
char *keys[9] = {"if","else","do","while","for","int","double","float","short"};
//系统保留关键词数组
while((ch=fgetc(fp)) != '#'){
if(ch==' '){
//状态变化 临时字符串以' \0 '结尾
if((status == 1) ||(status == 2)){
temp[cur_pointer] = '\0';
//结尾后位置归0 将字符串拷贝到主字符串数组作永久保存
cur_pointer = 0;
//拷贝字符串 从临时到主
copy_element(elements,i,temp,status,syn,keys);
i++;
}
status=0;
continue;
//如果是字母 可能是变量名、函数名或保留关键字
} else if((ch>'a' && ch<'z') || (ch>'A' && ch<'Z')){
if(status == 2){
temp[cur_pointer] = '\0';
//位置归0
cur_pointer = 0;
//拷贝字符串 从临时到主
copy_element(elements,i,temp,2,syn,keys);
i++;
}
status=1;
temp[cur_pointer++] = ch;
} else if(ch>'0' && ch<'9'){
if(status == 1){
temp[cur_pointer] = '\0';
cur_pointer = 0;
//拷贝字符串 从临时到主
copy_element(elements,i,temp,1,syn,keys);
i++;
}
status = 2;
temp[cur_pointer++] = ch;
} else {
//第三种字符就直接存入主字符串数组 不放入临时字符
if((status == 1) || (status == 2)){
temp[cur_pointer] = '\0';
cur_pointer = 0;
//拷贝字符串 从临时到主
copy_element(elements,i,temp,status,syn,keys);
i++;
}
status = 3;
switch(ch){
case '<':
status__=24;
elements[i] = "<";
syn[i] = 24;
i++;
break;
case '>':
if(status__==24){
//操作符匹配结束 status__置0
status__ = 0;
elements[--i] = "<>";
syn[i] = 19;
} else {
elements[i] = ">";
syn[i] = 23;
status__ = 23;
}
i++;
break;
case '=':
if(status__ == 22){
status__ = 0;
elements[--i] = "==";
syn[i] = 18;
} else if(status__ == 23){
status__ = 0;
elements[--i] = ">=";
syn[i] = 21;
}else if(status__ == 24){
status__ = 0;
elements[--i] = "<=";
syn[i] = 20;
} else {
status__ = 22;
elements[i] = "=";
syn[i] = 22;
}
i++;
break;
case '+':
elements[i] = "+";
syn[i] = 12;
break;
case '-':
elements[i] = "-";
syn[i] = 13;
break;
case '*':
elements[i] = "*";
syn[i] = 14;
break;
case '/':
elements[i] = "/";
syn[i] = 15;
break;
case '?':
elements[i] = "?";
syn[i] = 16;
break;
case ':':
elements[i] = ":";
syn[i] = 17;
break;
case ';':
elements[i] = ";";
syn[i] = 25;
break;
}
}
}
//test
int m=0;
for(m=0;m<i;m++){
printf("%s","(");
printf("%s",elements[m]);
printf("%s",",");
printf("%d",syn[m]);
printf("%s",")\n");
}
}