Adding 62-Unique-Paths.c

c/62-Unique-Paths.c

@@ -0,0 +1,30 @@
+int dp[105][105] = {};
+
+int ways(int posX, int posY, int m, int n)
+{
+    if(posX == m-1 && posY == n-1) return 1;
+
+    if(posX >= m || posY >= n) return 0;
+
+    if(dp[posX][posY] != -1) return dp[posX][posY];
+
+    int right = ways(posX + 1, posY, m, n); // moves to right corner.
+
+    int bottom = ways(posX, posY + 1, m, n);// moves to bottom corner.
+
+    dp[posX][posY] = right + bottom;
+
+    return dp[posX][posY];
+}
+
+int uniquePaths(int m, int n) {
+
+    // Initializing the dp array with -1 value.
+    for(int i = 0; i < 105; i++){
+        for(int j = 0; j < 105; j++) dp[i][j] = -1;
+    }
+
+    int ans = ways(0, 0, m, n);
+
+    return ans;
+}