【題目敘述】https://zerojudge.tw/ShowProblem?problemid=e573
【解題想法】
- 因為每個數字介於1到20之間（均為正數），
- 最大值：先加再乘
- 最小值：先乘再加
- 【範例】4*18+14+7*10
- 最大值 = 4 * (18 + 14 + 7) * 10 = 1560
- 最小值 = (4 * 18) + 14 + (7 * 10) = 156
#include <iostream>
#include <stack>
using namespace std;
long long MAX(string s){
stack <long long> stk;
char op;
long long x = 0, N = 0;
for (int i = 0; i < s.size(); i++){
if ('0' <= s[i] && s[i] <= '9'){
x = x * 10 + (s[i] - '0');
} else {
op = s[i];
if (op == '+') {
N += x;
x = 0;
} else {
stk.push(N + x);
N = 0;
x = 0;
}
}
}
stk.push(N + x);
long long ans = 1;
while (!stk.empty()){
ans *= stk.top();
stk.pop();
}
return ans;
}
long long MIN(string s){
stack <long long> stk;
char op;
long long x = 0, N = 1;
for (int i = 0; i < s.size(); i++){
if ('0' <= s[i] && s[i] <= '9'){
x = x * 10 + (s[i] - '0');
} else {
op = s[i];
if (op == '+') {
stk.push(N * x);
N = 1;
x = 0;
} else {
N *= x;
x = 0;
}
}
}
stk.push(N * x);
long long ans = 0;
while (!stk.empty()){
ans += stk.top();
stk.pop();
}
return ans;
}
int main() {
int T;
string s;
cin >> T;
while (T--){
cin >> s;
cout << "The maximum and minimum are ";
cout << MAX(s);
cout << " and ";
cout << MIN(s) << ".\n";
}
return 0;
}