inp = require('fs').readFileSync('/dev/stdin', 'utf8').split('\n')
s = inp.shift()
o = {a: 0, b: 0, c: 0}
f = true
for (i=0; i<s.length; i++) {
    o[s[i]] += 1
    if (o[s[i]] > 1) {
        f = false
        break;
    }
}
console.log(f ? 'Yes' : 'No')