Leetcode 2288 Apply Discount to Prices Solution in c++ | Hindi Coding Community

 

A sentence is a string of single-space separated words where each word can contain digits, lowercase letters, and the dollar sign '$'. A word represents a price if it is a sequence of digits preceded by a dollar sign.

For example, "$100", "$23", and "$6" represent prices while "100", "$", and "$1e5" do not.

You are given a string sentence representing a sentence and an integer discount. For each word representing a price, apply a discount of discount% on the price and update the word in the sentence. All updated prices should be represented with exactly two decimal places.

Return a string representing the modified sentence.

Note that all prices will contain at most 10 digits.

 

Example 1:

Input: sentence = "there are $1 $2 and 5$ candies in the shop", discount = 50

Output: "there are $0.50 $1.00 and 5$ candies in the shop"

Explanation: 

The words which represent prices are "$1" and "$2". 

- A 50% discount on "$1" yields "$0.50", so "$1" is replaced by "$0.50".

- A 50% discount on "$2" yields "$1". Since we need to have exactly 2 decimal places after a price, we replace "$2" with "$1.00".

Example 2:

Input: sentence = "1 2 $3 4 $5 $6 7 8$ $9 $10$", discount = 100

Output: "1 2 $0.00 4 $0.00 $0.00 7 8$ $0.00 $10$"

Explanation: 

Applying a 100% discount on any price will result in 0.

The words representing prices are "$3", "$5", "$6", and "$9".

Each of them is replaced by "$0.00".

string discountPrices(string &s, int dis) {

string res;

for (int i = 0, j = 0; i < s.size(); ++i) {

res += s[i];

if (s[i] == '$' && (i == 0 || s[i - 1] == ' ')) {

for (j = i + 1; j < s.size() && isdigit(s[j]); ++j) ;

if (j - i > 1 && (j == s.size() || s[j] == ' ')) {

long long p = (100 - dis) * stoll(s.substr(i + 1, j - i - 1));

res += to_string(p / 100) + "." + (p % 100 < 10 ? "0" : "") + to_string(p % 100);

i = j - 1;

}

}

}

return res;

}