Go: package main

import (
	"fmt"
	"math"
)

func main() {
	var M, N, P int
	for {
		fmt.Scan(&N, &M, &P)
		if N == 0 && M == 0 && P == 0 {
			return
		}

		arr := make([]int, N)
		sum := 0
		for i := 0; i < N; i++ {
			var po int
			fmt.Scan(&po)
			arr[i] = po
			sum += po
		}

		if arr[M-1] == 0 {
			fmt.Println(0)
		} else {
			fmt.Println(math.Floor(float64(sum * (100 - P) / arr[M-1])))
		}
	}
}

C++: #include <algorithm>
#include <complex>
#include <cstdlib>
#include <ctime>
#include <iomanip>
#include <iostream>
#include <map>
#include <math.h>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>

using namespace std;
#define SAY_YES cout << "YES" << endl;
#define SAY_Yes cout << "Yes" << endl;
#define SAY_NO cout << "NO" << endl;
#define SAY_No cout << "No" << endl;
#define IFYES(TRUE_OR_FALSE)   \
    if (TRUE_OR_FALSE)         \
    {                          \
        cout << "YES" << endl; \
    }                          \
    else                       \
    {                          \
        cout << "NO" << endl;  \
    }
#define IFYes(TRUE_OR_FALSE)   \
    if (TRUE_OR_FALSE)         \
    {                          \
        cout << "Yes" << endl; \
    }                          \
    else                       \
    {                          \
        cout << "No" << endl;  \
    }
#define IFyes(TRUE_OR_FALSE)   \
    if (TRUE_OR_FALSE)         \
    {                          \
        cout << "yes" << endl; \
    }                          \
    else                       \
    {                          \
        cout << "no" << endl;  \
    }
#define DEBUG_OUTPUT_ARRAY(XXX, ONE)                            \
    for (int i = 0; i < (ONE); i++)                             \
    {                                                           \
        cout << "DEBUG: i = " << i << " -> " << XXX[i] << endl; \
    }
#define DEBUG_OUTPUT_ARRAY2(XXX, ONE, TWO)                             \
    for (int i = 0; i < (ONE); i++)                                    \
    {                                                                  \
        cout << "<<< i = " << i << " >>>" << endl;                     \
        for (int j = 0; j < (TWO); j++)                                \
        {                                                              \
            cout << "DEBUG: j = " << j << " -> " << XXX[i][j] << endl; \
        }                                                              \
    }
#define DEBUG_OUTPUT_ARRAY2_BOX(XXX, ONE, TWO) \
    for (int i = 0; i < (ONE); i++)            \
    {                                          \
        cout << i << "  ";                     \
        for (int j = 0; j < (TWO); j++)        \
        {                                      \
            cout << XXX[i][j] << " ";          \
        }                                      \
        cout << endl;                          \
    }

typedef pair<long long int, long long int> pll;


const long long int mod = 1000000007;
const long long int INF = 1999999999;

long long int N,M,P,X[200],sum=0;
int main()
{
    cout << fixed << setprecision(18);
    cin>>N>>M>>P;
    while(N!=0){
        sum=0;
        for(long long int i = 1; i <= N; i++){
            cin>>X[i];
            sum+=(100-P)*X[i];
        }
        for(long long int i = 1; i <= N; i++){
            if(M==i){
                if(X[i]!=0)cout<<sum/X[i]<<endl;
                else{cout<<0<<endl;}
            }
        }
        cin>>N>>M>>P;
    }
}

C++: #include <bits/stdc++.h>

using namespace std;

int main() {

    int n, m, p, x;

    while(cin >> n >> m >> p, n | m | p) {

        int sum = 0;
        int hit = 0;

        for(int i = 1; i <= n; ++i) {
            cin >> x;
            sum += 100 * x;
            if(i == m) hit = x;
        }

        cout << (hit ? (sum * (100 - p) / 100) / hit : 0) << endl;

    }

}

C++: #include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <climits>
#include <cfloat>
#include <ctime>
#include <map>
#include <utility>
#include <set>
#include <iostream>
#include <memory>
#include <string>
#include <vector>
#include <algorithm>
#include <functional>
#include <sstream>
#include <complex>
#include <stack>
#include <queue>
#include <numeric>
#include <list>

using namespace std;

#ifdef _MSC_VER
#define __typeof__ decltype
template <class T> int __builtin_popcount(T n) { return n ? 1 + __builtin_popcount(n & (n - 1)) : 0; }
#endif

#define foreach(it, c) for (__typeof__((c).begin()) it=(c).begin(); it != (c).end(); ++it)
#define all(c) (c).begin(), (c).end()
#define rall(c) (c).rbegin(), (c).rend()
#define CLEAR(arr, val) memset(arr, val, sizeof(arr))

#define rep(i, n) for (int i = 0; i < n; ++i)

template <class T> void max_swap(T& a, const T& b) { a = max(a, b); }
template <class T> void min_swap(T& a, const T& b) { a = min(a, b); }

typedef long long ll;
typedef pair<int, int> pint;

const double PI = acos(-1.0);
const int dx[] = { 0, 1, 0, -1 };
const int dy[] = { 1, 0, -1, 0 };


int main()
{
	int n, m, p;
	while (scanf("%d%d%d", &n, &m, &p), n | m | p)
	{
		int x[128];
		rep (i, n)
			scanf("%d", x + i);
		if (x[m - 1])
			printf("%d\n", accumulate(x, x + n, 0) * (100 - p) / x[m - 1]);
		else
			puts("0");
	}
}

C++: #include<bits/stdc++.h>
#define endl '\n';
#define rep(i,n) for(int i=0; i<(n); i++)
using namespace std;
using ll = long long;
using P = pair<int,int>;
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize("Ofast")
constexpr ll INF = 1e18;
constexpr int inf = 1e9;
constexpr double INFD = 1e100;
constexpr ll mod = 1000000007;
constexpr ll mod2 = 998244353;
const double PI = 3.1415926535897932384626433832795028841971;
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
// ios::sync_with_stdio(false);
// cin.tie(nullptr);
// ---------------------------------------------------------------------------


int main(){
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  int N,M,P;
  cin >> N >> M >> P;
  while(N != 0){
    vector<int> A(N);
    int sum = 0;
    for(int i=0; i<N; i++){
      cin >> A[i];
      sum += A[i];
    }
    sum *= 100;
    sum -= sum*P/100;
    if(A[M-1] == 0){
      cout << 0 << endl;
    }else{
      cout << sum/A[M-1] << endl;
    }
    cin >> N >> M >> P;
  }
  return 0;
}