描述
There is a programming language with only four operations and one variable X:
++X and X++ increments the value of the variable X by 1. --X and X-- decrements the value of the variable X by 1.Initially, the value of X is 0.
Given an array of strings operations containing a list of operations, return the final value of X after performing all the operations.
测试用例
Input: operations = ["--X","X++","X++"]
Output: 1
Explanation: The operations are performed as follows:
Initially, X = 0.
--X: X is decremented by 1, X = 0 - 1 = -1.
X++: X is incremented by 1, X = -1 + 1 = 0.
X++: X is incremented by 1, X = 0 + 1 = 1.题解
不管是X—，—X还是X++，++X，只要判断中间字符的符号。
/**
* @param {string[]} operations
* @return {number}
*/
var finalValueAfterOperations = function(operations) {
let x = 0;
operations.forEach(item => {
if(item[1] === '+') {
x++;
} else if(item[1] === '-') {
x--;
}
});
console.log(x)
return x;
};结果
Accepted
259/259 cases passed (88 ms)
Your runtime beats 28.51 % of javascript submissions
Your memory usage beats 11.51 % of javascript submissions (40.6 MB)
