3.cpp

一次比赛的代码,有五道题,2,4比较基础,3题是模拟,1高精度,5树状dp

#include <cstdio>
#include <cstring>
#include <cmath>
#define max 81
char s[max],save[max];
int len,value[max],pv=0,inc=0;

bool isch(char a)
{
	 if (a<='z'&&a>='a') return 1;
	 else return 0;
}
/*bool test()
{
	int i,count=0;
	bool flag=1;
	for (i=1;i<len;i++)
	{
		if (s[i]==' ') continue;
		if (s[i-1]==s[i]) count++;
		else 
		{
			if (count%2==0) flag=0;
			count=0;
		}
		if (isch(s[i]))
		{
			if (isch(s[i-1])||isch(s[i+1])) flag=0;
			if ((s[i-1]==s[i-2])&&(s[i+1]==s[i+2])) flag=0;
		}
	}
	if (count%2==0) flag=0;
	return flag;
}*/

void get(int x,int y)
{
	int temp=0;
	bool before=0;
	char op;
	while (y>=x)
	{
		if ((x==y)&&(s[x]=='-'||s[x]=='+')) break;
		if (s[y]==' ') continue;
		if (s[y]==s[y-1])
		{
			if (s[y]=='-') {temp--;if (!before) inc++;}
			else {temp++;if (!before) inc--;}
			y-=2;
			continue;
		}
		if (isch(s[y])) {save[++pv]=s[y];y--;before=1;temp+=save[pv]-'a'+1;}
	}
	if (x==0) op='+'; else op=s[x];
	if (op=='+') value[pv]=temp;else value[pv]=0-temp;
}

int main()
{
	int i,begin,end,count,tot;
	while (gets(s))
	{
		if (s[0]=='\n') break;tot=0;pv=0;inc=0;
		len=strlen(s);begin=0;end=len-1;
		//if (test()) cout<<("expression error\n");
			count=0;
			for (i=0;i<len;i++)
			{
				if (s[i]==' ') continue;
				if (isch(s[i])) count++;
				if (count==2)
				{
					i-=2;
					get(begin,i);
					begin=i+1;
					count=0;
				}
				if ((s[i]=='-'&&s[i+1]=='+')||(s[i]=='+'&&s[i+1]=='-'))
				{
					if (begin!=0)
					{
						if ((i-begin)%2!=0)
						{
							get(begin,i);
							begin=i+1;
							i++;
							count=0;
						}
					    else 
						{
							get(begin,i-1);
							begin=i;
							count=0;
						}
					}
					else
					{
						if ((i-begin)%2==0)
						{
							get(begin,i);
							begin=i+1;
							i++;
							count=0;
						}
					    else 
						{
							get(begin,i-1);
							begin=i;
							count=0;
						}
					}
				}
				if (i==len-1)
				{
					get(begin,i);
				}
			}
			printf("Expression:%s\n",s);
			for (i=1;i<=pv;i++)
			{
				tot+=value[i];
			}
			printf("  value=%d\n",tot+inc);
			for (i=1;i<=pv;i++)
			{
				printf("  %c=%d\n",save[i],abs(value[i]));
			}
		
	}
	return 1;
}