let lines = [];
let reader = require('readline').createInterface({
  input: process.stdin,
  output: process.stdout
});

reader.on('line', function(line) {
  lines.push(line);
});

reader.on('close', function() {
  const S = lines[0].split('');
  let Sum = 0;

  for(let i = 0; i < S.length; i++) {
    // 正規表現で数値か判定する
    if(new RegExp('[0-9]').exec(S[i]) !== null) {
      Sum += parseInt(S[i]);
    }
  }
  console.log(Sum);
});