按键手机上按下的按钮数量

str.length()

//including the required libraries
#include <bits/stdc++.h>
using namespace std;
 
//storing thr reqd number of times a character should be pressed
const int arr[] = { 1, 2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3, 4, 1, 2, 3, 1, 2, 3, 4 };

//return the total number of times the button should be pressed
int numkeypresses(string str) {
   //initialising with count 
   int count = 0;
   //count the length of string 
   int len = str.length();
 
   // total key presses
   for (int i = 0; i < len; i++) {
      char ch = str[i];
      count+= arr[ch - 'a'];
   }
    
   cout << "Total number of key presses "<< count;
}
 
// Driver code
int main() {
   //input string
   string str = "tutorials";
   cout <<"Input String : "<< str << "\n" ;
   //calling the function to count the number of times key is pressed 
   numkeypresses(str);
 
   return 0;
}

Input String − tutorials
Total number of key presses 21