>>102 javascript
var f = s => {
var d = [...new Set(s)]
return d.length == 2
? ((a,b) => ({g:'c',c:'p',p:'g'})[a] == b)(d[0],d[1])
? s.match(new RegExp(d[0],'g')).length
: s.match(new RegExp(d[1],'g')).length
: 0;
}
console.log(f('gccgc')) //=> 2
console.log(f('ggggggg')) //=> 0
console.log(f('cppcppppccpppppc')) //=> 5
console.log(f('cppcppppccpgpppc')) //=> 0