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sptnk1: 2023-12-11 00:18:19

#include<iostream>
#include <stack>
#include<vector>
#include <queue>
using namespace std;
int lev1(char tem)
{
	if (tem == '(')
		return 1;
	if (tem == '*' || tem == '/')
		return 5;
	if (tem == '+' || tem == '-')
		return 3;
	if (tem == ')')
		return 6;
	return 0;
}
int lev1(string tem)
{
	if (tem == "(")
		return 1;
	if (tem == "*" || tem == "/")
		return 5;
	if (tem == "+" || tem == "-")
		return 3;
	if (tem == ")")
		return 6;
	return 0;
}
int lev2(string tem)
{
	if (tem == "(")
		return 6;
	if (tem == "*" || tem == "/")
		return 4;
	if (tem == "+" || tem == "-")
		return 2;
	if (tem == ")")
		return 1;
	return 0;
}
vector<string> back(vector<string> middle)
{
	stack<string> tem;
	tem.push("0");
	vector<string> bac;
	int i = 0;
	while (!tem.empty())
	{
		if(i<middle.size())
		{
			if (lev1(middle[i]) == 0)
			{
				bac.push_back(middle[i]);
				i++;
			}
			else {
				string te = tem.top();
				if (lev2(middle[i]) > lev1(te))
				{
					tem.push(middle[i]);
					i++;
				}
				else if (lev2(middle[i]) < lev1(te))
				{
					bac.push_back(te);
					tem.pop();
					if (tem.size() == 1 && i == middle.size())
						break;
				}
				else if (lev2(middle[i]) == lev1(te))
				{
					if (te == "(")
					{
						i++;
					}

					tem.pop();
				}
			}
		}
		else {
			while (tem.size() != 1)
			{
				bac.push_back(tem.top());
				tem.pop();
			}
			break;
		}
	}
	
	return bac;
}
vector<string> creat(string tem)
{
	vector<string> cre;
	queue<char> one;
	one.push(tem[0]);
	int i = 1;
	string two = "";
	while (!one.empty())
	{
		if (i != tem.size())
		{
			if (lev1(tem[i]) == lev1(one.front()))
			{
				one.push(tem[i]);
				i++;
			}
			else {
				two = "";
				while (!one.empty())
				{
					two += one.front();
					one.pop();
				}
				cre.push_back(two);
				one.push(tem[i]);
				i++;
			}
		}
		else {
			if(one.front()!='#')
			{
				two = "";
				while (!one.empty())
				{
					if (one.front() != '#')
					{
						two += one.front();
					}
					one.pop();
				}
				cre.push_back(two);
			
			}
			break;
			}
	}
	return cre;
}
int si(string tem)
{
	int a = 0;
	for (int i = 0; i < tem.size(); i++)
	{
		a = a * 10 + tem[i] - '0';
	}
	return a;
}
int calu(vector<string> tem)
{
	stack<int> a;
	int i = 1;
	a.push(si(tem[0]));
	while (!a.empty()&&i!=tem.size())
	{
			if (lev1(tem[i]) == 0)
			{
				a.push(si(tem[i]));
			}
			else if (tem[i] == "+")
			{
				int b = a.top();
				a.pop();
				b += a.top();
				a.pop();
				a.push(b);
			}
			else if (tem[i] == "-")
			{
				int b = a.top();
				a.pop();
				b = a.top()-b;
				a.pop();
				a.push(b);
			}
			else if (tem[i] == "*")
			{
				int b = a.top();
				a.pop();
				b *= a.top();
				a.pop();
				a.push(b);
			}
			else if (tem[i] == "/")
			{
				int b = a.top();
				a.pop();
				b = a.top()/b;
				a.pop();
				a.push(b);
			}
			i++;
	}
	return a.top();
}
int main()
{
	int n;
	string tem;
	cin >> n;
	for (int i = 0; i < n; i++)
	{
		cin >> tem;
		vector<string> tem1 = creat(tem);
		vector<string> tem2 = back(tem1);
		cout << calu(tem2) << endl;
	}
	
}

61521314吴政邦: 2022-04-28 16:26:58

#include<iostream>
#include<string>
#include<stack>
using namespace std;
const int maxn = 100;
int in(char a) {
    switch (a) {
    case '#':return 0;
    case '(':return 1;
    case '*':case'/': return 5;
    case'+':case'-':return 3;
    case')':return 9;
    }
}
int out(char a) {
    switch (a) {
    case '#':return 0;
    case '(':return 9;
    case '*':case'/': return 4;
    case'+':case'-':return 2;
    case')':return 1;
    }
}

int Operate(int m, int n, char x) {
    if (x == '+')
        return m + n;
    if (x == '-')
        return n - m;
    if (x == '*')
        return m * n;
    if (x == '/')
        return n / m;
}
int cal() {
    stack <int> OPND;  
    stack <char> OPTR;  
    OPTR.push('#');
    char ss[2] = "#"; 
    char s[maxn];
    cin >> s;
    int len = strlen(s) + strlen(ss) + 1;
    strcat_s(s,len,ss); 
    char c = s[0];
    int k = 1;
    while (c != '#' || OPTR.top() != '#') {   
        int y = 0;
        if (c >= '0' && c <= '9') {
            while (c >= '0' && c <= '9') {  
                y = y * 10 + (c - '0');
                c = s[k++];
            }
            OPND.push(y);  
        }
        else {
            if (out(c) > in(OPTR.top())) {
                OPTR.push(c);
                c = s[k++];
            }
            if (out(c) == in(OPTR.top())) {
                OPTR.pop();
                c = s[k++];
            }
            if (out(c) < in(OPTR.top())){
                char x = OPTR.top(); OPTR.pop();
                int m = OPND.top(); OPND.pop();
                int n = OPND.top(); OPND.pop();
                OPND.push(Operate(m, n, x));
            }
        }
    }
    return OPND.top();
}
int main() {
    int T; cin >> T;
    int* k = new int[T];
    for (int i = 0; i < T; i++) {
        k[i] = cal();
    }
    for (int i = 0; i < T; i++) {
        cout << k[i] << endl;
    }
    return 0;
}

61520218: 2021-05-19 17:46:56

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