Submission #3418055

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Source Code Expand

#include <iostream>
#include <string>
#include <vector>

using namespace std;

bool dfs(int d, string num, int result, string exp)
{
  if (d == num.size()) {
    if (result == 7) {
      cout << exp << "=7" << endl;
      return true;
    }
    return false;
  }

  if (dfs(d + 1, num, result + (num[d] - '0'), exp + '+' + num[d]))
    return true;
  if (dfs(d + 1, num, result - (num[d] - '0'), exp + '-' + num[d]))
    return true;
  return false;
}

int main()
{
  string num;
  cin >> num;
  dfs(1, num, num[0] - '0', ""s + num[0]);

  return 0;
}

Submission Info

Judge Result