AC 042, started from the beginning of atcoder with rust to practice my rust

atcoder/beginner_contests/abc042/src/bin/d.rs

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+use proconio::input;
+
+const MAX: u128 = u128::pow(10, 9) + 7;
+
+fn main() {
+    input!{
+        h: u128,
+        w: u128,
+        a: u128,
+        b: u128,
+    };
+
+    // Ok it seems like this way is too naive for this problem and I actually have
+    // to do some magic with combinations or something else I haven't even thought of
+
+    // But I don't think you can do combinations because you need to divide big numbers
+    // and you can't do that with modulo iirc
+
+    let mut dp = vec![vec![0; w as usize]; h as usize];
+    for i in 0..(h-a) {
+        dp[i as usize][0] = 1;
+    }
+    for j in 0..w {
+        dp[0][j as usize] = 1;
+    }
+
+    for i in 1..h {
+        for j in 1..w {
+            if !(i >= h - a && j < b) {
+                dp[i as usize][j as usize] = (dp[(i - 1) as usize][j as usize] + dp[i as usize][(j - 1) as usize]) % MAX;
+            }
+        }
+    }
+
+    // for row in &dp {
+    //     for cell in row {
+    //         print!("{} ", {cell});
+    //     }
+    //     print!("\n");
+    // }
+
+    println!("{}", {dp[(h-1) as usize][(w-1) as usize]});
+}