# leetcode\_848

We have a string S of lowercase letters, and an integer array shifts.

Call the shift of a letter, the next letter in the alphabet, (wrapping around so that 'z' becomes 'a').

For example, shift('a') = 'b', shift('t') = 'u', and shift('z') = 'a'.

Now for each shifts\[i] = x, we want to shift the first i+1 letters of S, x times.

Return the final string after all such shifts to S are applied.

Example 1:

Input: S = "abc", shifts = \[3,5,9] Output: "rpl" Explanation: We start with "abc". After shifting the first 1 letters of S by 3, we have "dbc". After shifting the first 2 letters of S by 5, we have "igc". After shifting the first 3 letters of S by 9, we have "rpl", the answer. Note:

1 <= S.length = shifts.length <= 20000 0 <= shifts\[i] <= 10 ^ 9

## Solutions

1. **straight forward**

```cpp
class Solution {
public:
    string shiftingLetters(string S, vector<int>& shifts) {
        vector<int> inc(S.size());
        int shift = 0;
        for (int j = shifts.size() - 1; j >= 0; j--) {
            shift += shifts[j] % 26;
            S[j] = 'a' + (S[j] - 'a' + shift + 26) % 26;
        }
        return S;
    }
};
```