C - Detective Task

https://codeforces.com/contest/1675/submission/155959148

Codeforces/1675/C/C.cpp

@@ -0,0 +1,41 @@
+#include <iostream>
+#include <string>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 2e5 + 5;
+
+int t, sum[N][2], ans;
+std::string s;
+
+int main() {
+    std::ios::sync_with_stdio(false);
+
+    cin >> t;
+
+    while (t--) {
+        ans = 0;
+
+        cin >> s;
+
+        for (int i = 0; i < s.size(); i++) {
+            if (i) {
+                sum[i][0] = sum[i - 1][0] + (s[i] == '0');
+                sum[i][1] = sum[i - 1][1] + (s[i] == '1');
+            } else {
+                sum[i][0] = s[i] == '0';
+                sum[i][1] = s[i] == '1';
+            }
+        }
+
+        for (int i = 0; i < s.size(); i++) {
+            ans += (sum[i][0] - (s[i] == '0')) == 0 && (sum[s.size() - 1][1] == sum[i][1]);
+        }
+
+        cout << ans << endl;
+    }
+
+    return 0;
+}