Solution.go

func isInterleave(s1 string, s2 string, s3 string) bool {
    if len(s1)+len(s2) != len(s3) {
        return false
    }
     n,m := len(s1), len(s2)
     dp := make([][]bool, n+1)
     for i := 0; i < len(dp); i++ {
         dp[i] = make([]bool, m+1)
     }
     dp[0][0] = true
     for i := 1; i <= n; i++ {
         dp[i][0] = dp[i-1][0] && (s1[i-1] == s3[i-1])
     }
     for i := 1; i <= m ; i++ {
         dp[0][i] = dp[0][i-1] && (s2[i-1] == s3[i-1])
     }
     for i := 1; i <= n; i++ {
         for j := 1; j <= m; j++ {
             dp[i][j] = dp[i-1][j] && (s1[i-1] == s3[i-1+j]) || dp[i][j-1] && (s2[j-1] == s3[i+j-1])
         }
     }
     return dp[n][m]
}