tessoku-book a45, b45

tessoku-book/src/bin/a45.rs

@@ -1,10 +1,35 @@
-use proconio::{input, marker::Usize1};
+use proconio::{input, marker::Chars};
 
 fn main() {
     input! {
-        n: usize,
-        a: [Usize1; n],
+        _n: usize,
+        c: char,
+        a: Chars,
     };
-    let ans = n - a.len();
-    println!("{}", ans);
+    // W: 0
+    // B: 1
+    // R: 2
+    //
+    // W + W = W = 0 + 0 = 0
+    // B + B = R = 1 + 1 = 2
+    // R + R = B = 2 + 2 = 1 (mod 3)
+    // W + B = B = 0 + 1 = 1
+    // W + R = R = 0 + 2 = 2
+    // B + R = W = 1 + 2 = 0 (mod 3)
+    let f = |ch: char| -> usize {
+        match ch {
+            'W' => 0,
+            'B' => 1,
+            'R' => 2,
+            _ => unreachable!(),
+        }
+    };
+
+    let mut sum = 0_usize;
+    for a_i in a {
+        sum += f(a_i);
+        sum %= 3;
+    }
+    let ans = sum == f(c);
+    println!("{}", if ans { "Yes" } else { "No" });
 }

tessoku-book/src/bin/b45.rs

@@ -1,10 +1,11 @@
-use proconio::{input, marker::Usize1};
+use proconio::input;
 
 fn main() {
     input! {
-        n: usize,
-        a: [Usize1; n],
+        a: i64,
+        b: i64,
+        c: i64,
     };
-    let ans = n - a.len();
-    println!("{}", ans);
+    let ans = (a + b + c) == 0;
+    println!("{}", if ans { "Yes" } else { "No" });
 }