0-1 knapsack problem by DP

#include<iostream>
using namespace std;

int KnapSack(int tot_wt,int wt[],int val[],int n){
  int max_val[n+1][tot_wt+1],res=0;
  for(int i=0;i<=n;i++){
    for(int j=0;j<=tot_wt;j++){
      if(i==0|| j==0)
            max_val[i][j]=0;
      else{
        int x=(wt[i-1]<=j)? val[i-1]+max_val[i-1][j-wt[i-1]]:0;
        max_val[i][j]=max(x,max_val[i-1][j]);
        }
        if(res<max_val[i][j])
            res=max_val[i][j];
      }
    }
    return res;  // or return max_val[n][tot_wt];
  }

int main(){
  int val[] = { 60, 100, 120 };
  int wt[] = { 10, 20, 30 };
  int W = 50;
  int n = 3;
  cout << KnapSack(W, wt, val, n);
  return 0;
  }