rest operator

// Without rest parameter
function fun(a, b){
return a + b;
}
console.log(fun(1, 2)); // 3  takes only 1st 2 parameters for sum of a + b
console.log(fun(1, 2, 3, 4, 5)); // 3


// es6 rest parameter 
function fun(...input){ 
let sum = 0; 
for(let i of input){ 
sum+=i; 
} 
return sum; 
} 
console.log(fun(1,2)); //3 
console.log(fun(1,2,3)); //6 
console.log(fun(1,2,3,4,5)); //15  





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