題目
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.
Example
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.
- 題意: 看到"+“要加1 看到”-" 要減一
解法
func finalValueAfterOperations(operations []string) int {
res := 0
for _, v := range operations {
if v[1] == '-' {
res--
} else {
res++
}
}
return res
}
- 加個測試，看看結果是不是如預期
import (
"github.com/stretchr/testify/assert"
"testing"
)
func Test_finalValueAfterOperations(t *testing.T) {
res := finalValueAfterOperations([]string{"--X", "X++", "X++"})
assert.Equal(t, 1, res)
}