#include <iostream>
#include <vector>
#include <string>
#include <iomanip>
#include <queue>
#include <cmath>
#include <algorithm>
#include <tuple>
#include <iomanip>
#include <stdio.h>
#include <numeric>
#include <map>
#include <math.h>
#include <bitset>

#define int long long
#define ull unsigned long long
#define all(a) a.begin(), a.end()
#define pii pair<int, int>
#define pb push_back

using namespace std;

const double PI = 3.14159265358;

long long gcd(long long a, long long b) {
    if (a==0) return b;
    if (b==0) return a;
    if (a>b) return gcd(a%b,b); else return gcd(b%a,a);
}
int prime(int p) { // 1 - простое
    for (int i=2;i*i<=p;i++) {
        if (p%i==0 && i<p) return 0;
    }
    return 1;
}

double s(int x1, int y1, int x2, int y2) {
    return sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
}

bool q(int x, int y) {
    return ((x % 2 == 0 or y % 2 == 0) and not (x % 2 == 0 and y % 2 == 0));
}

signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    string s;
    getline(cin, s);
    int op = -1, eq = -1;
    bool correct = true;
    vector<int> m;
    int n = s.size();
    for (int i = 0; i < n; i++) {
        if (s[i] == '-') m.pb(i);
    }
    if (find(all(s), '-') != s.end()) op = find(all(s), '-') - s.begin();
    if (find(all(s), '+') != s.end()) op = find(all(s), '+') - s.begin();
    if (find(all(s), '*') != s.end()) op = find(all(s), '*') - s.begin();
    if (find(all(s), '/') != s.end()) op = find(all(s), '/') - s.begin();
    if (find(all(s), '=') != s.end()) eq = find(all(s), '=') - s.begin();
    else {correct = false;}
    if (op == find(all(s), '-') - s.begin() and m[0] == 0) {op = m[1];}
    bool negf=false, negs=false, negt=false;
//    cout << op << "\n" << eq << "\n";;
    if (op == 0 or op > eq or op + 1 == eq or eq == n - 1 or op == -1 or eq == -1) {correct = false;
//     cout << "false\n";
     }
    int first = 0, second = 0, third = 0;
    for (int i = 0; i < op; i++) {
        if (s[i] == '-' and i == 0) {negf = true; continue;
//         cout << "first\n";
        }
        if ((s[i] == '0' and i == 0 and op != i + 1) or (s[i] == '0' and i == 1 and negf == true and op != i + 1)) {
            correct = false;
            break;
        }
        if (s[i] >= '0' and s[i] <= '9') first = first * 10 + (s[i] - '0');
        else {correct = false;
//         cout << "false first\n" << s[i] << "\n";
        }
    }
    for (int i = op + 1; i < eq; i++) {
        if (s[i] == '-' and i == op + 1) {negs = true; continue;
//         cout << "second\n";
         }
        if ((s[i] == '0' and i == op + 1 and eq != i + 1) or (s[i] == '0' and i == op+2 and negs==true and eq != i + 1)) {
            correct = false;
            break;
        }
        if (s[i] >= '0' and s[i] <= '9') second = second * 10 + (s[i] - '0');
        else {correct = false;
//         cout << "false second\n";
         }
    }
//    cout << correct << "\n";
    for (int i = eq + 1; i < n; i++) {
        if (s[i] == '-' and i == eq + 1) {negt = true; continue;
//         cout << "third" << "\n";
         }
         if ((s[i] == '0' and i == eq + 1 and n != i + 1) or (s[i] == '0' and i == eq + 2 and negt == true and n != i + 1)) {
            correct = false;
            break;
         }
        if (s[i] >= '0' and s[i] <= '9') third = third * 10 + (s[i] - '0');
        else {correct = false;
//         cout << "false third\n";
         }
    }
//    cout << correct << "\n";
    if (first == 0 and negf == true and op == 1) correct = false;
    if (second == 0 and negs == true and eq - op == 2) correct = false;
    if (third == 0 and negt == true and n - eq == 2) correct = false;
    if (negf) first = -first;
    if (negs) second = -second;
    if (negt) third = -third;
    if (correct) {
        if (s[op] == '+') {
            if (first + second == third) cout << "YES";
            else cout << "NO";
        } else if (s[op] == '-') {
            if (first - second == third) cout << "YES";
            else cout << "NO";
        } else if (s[op] == '*') {
            if (first * second == third) cout << "YES";
            else cout << "NO";
        } else if (s[op] == '/') {
            if ((double)first / second == (double)third) cout << "YES";
            else cout << "NO";
        } else cout << "ERROR";
    } else cout << "ERROR";
}